Carb vs. EFI
 

I love riding in the mountains in Colorado, where I live. One ride I like in particular starts at about 5300 ft. and goes over a 12,500 ft. pass. Almost any ride I pick will involve 15mph hairpin turns and steep climbing to get to a 10,000-11,000 ft pass.
I am planning several multi-day rides this summer, mostly on tarmac, and a 7500+ mile ride to Alaska and back in August, so I have two competing issues--ease of maintenance/repair, on one hand, and adaptability to significant altitude changes on the other hand. I'm pretty happy with this 650cc size motor as good all-around for my needs.

I ride a BMW F650GS Dakar right now (EFI), but she's a comparatively heavy, tall girl with a high C of G, which makes her a little awkward in the tight turns I see so often. I'm thinking of changing bikes, maybe to a DR650se, (more than 50# lighter and a lower C of G) but I'm wondering if I should even consider a carb'd bike because of the altitude I regularly ride. Any thoughts or guidance between these two bikes in light of these issues would be appreciated.

Hi Uhuru
I have no particular opinion on the topic. All the bikes I own have carbs, but that's more to do with me being cheap and riding old bikes, rather than not liking (more modern) efi. If you put

site:www.horizonsunlimited.com efi carbs

into a google search box you get lots of threads where this topic has been discussed already. Maybe there is some useful advice there?

cheers
Chris

Modern EFI is fantastic !!

It deals with altitude really well and the ecomony vs carbs is brilliant..

It used the be that EFI was snatchy while a nicely tuned carb was smooth but it's near impossible to tell these days.

The only downsides to efi is the extra electronics involved but it doesn't HAVE to be so complicated and is VERY reliable in modern bikes.

The "man down the pub" will always say "im never riding one of those FI bikes with all that stuff to go wrong"... Well, have you ever seen inside a CV Carb ?? All those springs, jets, needles, valves and diaphrams.


Anyway, back to the altitude issue... It's not like a carbed bike won't run or break down at that change in height.. You may not even notice it !

EFI has my vote any day. As mentioned by Ted, today's electronic is bullet proof.



P.S.: :welcome: to the HUBB!

+1 for EFI

+2 for :welcome: to the HUBB

It all depends which bike for EFI --my VStrom is not smooth at low rpm.
You are not going to get any more power out of the bike by using EFI just more convenience .If you don't like rejetting then steer clear of carbs .

Thanks
 

I appreciate the guidance from everyone. Thank you. I did check other threads but didn't see one about the altitude issue. These replies are very helpful.

FI is the go.

Diesel submarines, Piston engine aircraft etc all run fuel injection. Far more mission critical equipment than adventure motorcycles run fuel injection. Its been around since 1925 and widespread in many applications since the second world war. Its not some new fangled technology. Even Electronic FI has been around for 50 years.

They havent sold a car with carbs in the US since 1992 ... if anyone thinks 1970s carbed cars have more reliable induction than modern EFI cars, they are living in a dream.

EFI all the way. ON top of it all, a fuel injector is actually a far more simple piece of kit than a carb. There is effectively only one moving part in the injector.

I think the need to use carbs is one of the great adventure motorcycling wives tales.

Thanks
 

Thanks, colebatch. Very helpful. People keep writing how easy carbs are to work on compared to EFI, but others point out EFI is more efficient and more reliable.
Now, get some sleep! By my watch it looks like it was about 4:00 a.m. in UK when you wrote this!

That may be so, but I am in Canada right now :)

" if anyone thinks 1970s carbed cars have more reliable induction than modern EFI cars, "

Well I have to differ , I have a Dodge Ramcharger with an EFI system that is very unreliable and drinks fuel much more than my friend's carbed version .
I am waiting to find a good carb unit to put in it .Principly because a carb is a mechanical device that I can see with my own eyes ,fix with simple tools .
When they are new both systems are reliable but when they get old ,well a new or rebuilt carb cures most ills .You can hunt for ever for that frayed wire,, or cracked piece of plastic on an EFI system .
I don't have any preference one way or the other on a bike but I know that a gravity fed carb is more fixable and therefore ,in the long term, more reliable for a stone age mechanic like myself .

Another thing you have to consider is the engine characteristics ,many bikes run very lean to get around emissions tests .VStroms have a notorious weak spot at around 3500 rpm .Now to fix that you have to get the computer remapped with a power commander and that costs about $300 .If the bike had carbs ,all I would have to do is raise the needles to richen up the mixture and that costs nothing but my time .

:confused1: :confused1: Seriously?

Let me google that for you

Don't use the HUBB search, it doesn't work (well).

:euro: Dear chap there are 4,370 such topics.

Absolutely... If only some of the major manufactures would put a decent, reliable fuel pump in their bikes to compliment it as the FI is so reliant on this.



You can get good and bad FI as you know. Depends how much R&D they manufacturer can be bothered putting into the mapping.

Carbs are still WAY easier for the home mechanic to tune and fettle with and probably why they are still standard kit accross the board on MX/Enduro bikes..Although, expect that to change very soon. I think Honda are making their whole CR series FI this or next year !!

Blimey !!

Actually you don´t, because the standard EFI box is programmable. You´ll just need to connect it to a laptop with proper software on it (this is usually done at the dealer during other maintenance) and adjust fuel amounts just a little at low rpm on partial throttle openings.

But I´m sure the dealers, who sell Power commander or similar systems would disagree, it is their business afterall!!

For me, it´s FI all the way nowadays, simple as that. I´ve had several carb´d bikes (and cars) during the years, and in FI, both functionality and dependability are just superior, even if/when planning an overland-trip to faraway countries.

I don't think you can just split this carbs and FI. My MZ has one carb with maybe three seals and half a dozen moving parts. It either works or it doesn't, you can tune it with a screwdriver and a metal rule so long as you can count to 5. The pair of things on the Bonneville have dozens or O-rings, linkages, diaphragms and goodness knows what else and require vacuum gauges and some sort of surgical manipulator to tune them. The FI on the Brick is a series of components that can be tested with a multimeter.

I'd ditch the carbs on the Bonneville for FI tomorrow if I could afford the newer bike.

For those terrified of the black box: I worked for the largest manufacturer of truck ABS ECU's in the world for 12 years. I that time, in the UK, I accepted warranty claims on one ECU. I saw dozens of claims a month from dealers who were too stupid or mean to get the right diagnostic kit and had started swapping parts. I saw a few great examples from owners who couldn't read, such as the one with burn marks from the welding set earth. I once travelled 400 miles to change a fuse on a bus the dealer had fitted three ECU's to in the space of a week. There is no shortage to idiots who'll blame what they can't understand, the trick is simply not to deal with them. ECU's never ever fail when compared to plugs, other bits of wiring and petrol soaked O-rings. Given my 1984 BMW has FI, we really should be getting out of this era with FI by now.

Andy

eternal discussion ...
 

It is in my opnion. A bike with a well-tuned carburettor is as good as a bike with a well-tuned FI system. The statement also applies if you replace the "well" twice with "badly".
FI does have more components which are 'distributed' over the bike and interconnected by wiring - increasing the chance of malfunction. As does the number of components increase the chance of malfunction. That said, FI systems are very very reliable nowadays - almost all the cars you see on the road are fuel injected and how many of them break down due to a fault in the FI system?

For sheer reliability, I'd still choose a carb, as they tend to be very reliable. Interesting for the OP: a CV carb (constant vacuum) does not need altitude adjustment - the adjustment is 'built-in' in it's operating principle.

I did however just change from a carburetted bike to an FI bike - and I like it. Reading through the numerous boards all over the internet I dare say that the amount of expertise shown by those tinkering with carbs and those tinkering with FI is about the same - and would not encourage me to have my bike worked on by the posters.

A

Hi Pecha72,
Whether you use a power commander ,use your own computer with the correct program or go to the dealer to have the fueling altered [ IF he can do it properly ] .The principle is the same .
My point is that you are stepping up the cost and utilising technology that is beyond the brain and screwdriver .
I don't go to dealers ,because they are expensive and in the most part incompetent .

Most ECU's aren't remappable anyway. Some can be flashed with new firmware but only by maps supplied BY the manufacturer of the bike.

This is exactly why power commanders exist !!

I have to agree with Dodger... 99% of dealers wouldnt know what to do with a rolling road and a power commader but there are websites full of maps with different sets ups that you can download. For that, I really like FI as it's pretty much plug and play.

It took less than 5 minutes to adjust my Vstrom´s ECU (to fix that running at low revs), so cost isnt an issue here. And I know you can make more precise adjustments with a PC, so if I was building a race bike, then it might make sense. A Vstrom can run just fine without it.

I don´t know about the quality of the dealers in your area, but that adjustment is really very basic.

Complicated technology? Well, maybe, if you compare to a screwdriver, but like pointed out here, FI´s actually been around for ages, it works really well, and has clear advantages compared to what was before.

Shop charges are around $95 to $110 an hour , one hour minimum charge .
I wouldn't trust them with my wheelbarrow !

Ride safe and prosper .:mchappy:

Thanks, TurboCharger
 

I obviously am not fluent with computer stuff and am inept at searching. I was not aware one could search the site using Google.

I joined as a Gold member to support the site, read posts for 10 months trying to learn and find my way around, and get spanked for my third post.

Sorry I irritated you. Anyway, I do appreciate you teaching me how to search. Thank you.

Difficult to improve on that combination, especially right now with fuel prices on the rise, the F650gs get's significantly better fuel efficiency compared to the carbed 650's.

The DR650se might be a bit lighter but it's still a fairly big tall bike.
If you want lighter and more peppy consider a WR250R, also a tall bike but a lot lighter weight.

The Dakar you got is a mighty good all-around bike. It's just a bit underpowered by my tastes.

Don't be disgruntled... The search function on the hubb is CR*P and oftens returns no results so there are plenty of questions asked over and over and over (by me too).

Welcome to the Hubb and long may you be a member :thumbup1:

Thanks, Touring Ed
 

Thank you for your encouragement. It's nice to feel welcomed.

I personally do not mind EFI at all. However, newer bikes with EFI tend to also have a lot of other electronics, which make (IMHO) service during a trip harder. Things like electronic ABS, FI dependent on catalyst readings, gear sensors, sensors for this, sensors for that.

While there is nothing _wrong_ with it, I do not know how to diagnose elaborate electronics issues in the field.

Hence I, personally, would rather take my '93 TransAlp on a big trip than a GS800.

Then again, YMMV...

Yeah.. That is a problem on many, but not all bikes !!!

I agree with your choice of travel bike though..... Electrics scare me too lol

Missed this thread completely when it was current. I originally trained in Electronic Engineering (used to work with military radio equipment) and although completely out of date the same principles can still be applied.

EFI wins hands down on the moving parts argument and with intelligent design is going to be much better in water (no float chaber or breather pipes). The problem lies in the engine management unit that controls the FI using input from various sensors and also controls ignition timing based on a stored algorithm. The algorithm can be altered on some bikes allowing better operation with low grade fuel for example. Electronics can fail for no good reason although apart from 'infant failures' most failures are agrevated by heat or water. Electronics are very light and cost very little to make especially if made in quantity and can also be made extremely rugged at virtually no extra cost. Unfortunately, the same is not true of the sensors and the connections to the sensors. For an ideal travel bike it seems to me that a manufacturer could easily make the electronics 100% redundant at very little extra cost to the end user. The same could be done for the sensors and the wiring although it may cost more. Redundancy would add nothing to the weight. Better on board diagnostics would be a useful facility so that when a failure does occur and your bike is running on the back up system you can order a replacement part to get the bike back to 100% as soon as possible.

Hi Colebatch

I am not a native English speaking guy, could you please explain what is the meaning of WIVES in this sentence ? ))))

I have a R80 GS Basic which is a great adventure motorcycle IMHO! which is running on carbs and I am a member of Euroheads Group too.

If it has real meaning of wife (s), my wife (s) don't know any tales about carbs !

:oops2:

Having ridden on and with a few different bikes over the Pyrenees between France and Spain (close to sea level up to 2500m) I have to say that FI is the way to go. The caveat is that the manufacturer must be experienced in FI:- I have been warned by someone with greater knowledge and experience than I that the system in certain orange bikes is not as robust as BMW's for example.

CCM 604 (air cooled rotax, delorto carb) was running a bit rough by 1000m and got worse as it climbed higher.
DRZ400S - CV carb, was also popping and farting and down on power.
BMW F650GS (single) as you know altitude seems not to affect it.
BMW G650X Challenge - No discernible difference in power but it uses even less fuel than normal.

The G650X series may be worth looking at. In the UK they never really caught on and it is possible to buy one for less than a late model F650GS (single). Practically the same engine you are used to but the bike has been on a 40kg diet.

From experience: the BMW runs fine without a cat, without a lambda sensor and you can even fit a 10% larger fuel injector in about 10 minutes. This gets round the very lean settings enforced by emissions regulations and improves running, at the expense of slightly increased fuel consumption of course.

FI is incomparably better than carburettion. The only negative to FI is that if your battery dies (including losing a single cell) then the FI is guaranteed to cease operation. However, putting this into context, there are many carburetted bikes that will also stop running if the battery dies.

+1. Just like to add to that that there are now batteryless FI systems available. Wish I could retrofit that. FI is amazing at altitude. You may have to down shift because of the powerloss, but it still purrs as normal.

After owning maybe a dozen bikes with carbs, I now own my first bike with EFI. No farting around with a choke, no blipping the throttle when starting the bike, no waiting for a cold engine to warm up, etc. Just push the starter button and it fires right up and runs smoothly. I think it's great!

Thank you very much Ted ;)

Got it

A wives tale is a false "perceived wisdom" handed down usually by older women.

Things like "if you wind the window down in your car and have moving air on your face, you are likely to catch a cold" and other rubbish like that. For a long time the perceived wisdom was that you needed an old bike and carburettors to ride around the world.

That has long since changed.

Sure you can still do it with an old bike and carbs, and there is nothing wrong with that, but the idea that you NEEDED carbs, or were somehow reckless and foolish to take a fuel injected bike has been proven terribly out of date.

The vast majority of bikes I have met in remote places all use EFI, and not one of them had a single issue with the EFI. I never met anyone who had to rebuild their injector on the road. I have met dozens and dozens who have partially or fully rebuilt their carb on the road. I never met anyone whose big bike trip was stopped because of failed ECU either. Not saying it never happens, just saying the reality (as opposed to the stories) for me is that EFI wins on pretty much every count every time. If you compare the amount of times an EFI system NEEDS to be tuned, modified, partially or fully rebuilt while on the road on a trip, compared to a carbed system, then you could only say that EFI is dozens of times more reliable than carbs.

The one bike to worry about is the issue prone 690 ... which seems to have a few fuel pump, fuel filter and voltage regulator issues.

I'd like to add (although this is based more on car experience than bikes, but I reckon it'll hold true) that the actual EFI system itself might be bullet-proof but there are a whole host of sensors that go with it, which in my book means more things that can go wrong or fail. Without the sensor arrays EFI wouldn't deliver the same benefits over carbs though - so it comes down to personal choice. I wouldn't be put off by either.

Then there's the issue of high pressure fuel pumps. My KLR doesn't have a fuel pump; users of certain fuel injected bikes carry spares, since without a working fuel pump they're dead in the water. Plus the pickup screens, which can become clogged. And the whole issue of complex electronics, which may rarely fail (but certainly do, from time to time). The question of bump starts with dead batteries. The flat spot/surge on acceleration. Et cetera. Plus the fact that with fuel injection comes all sorts of other, unrelated electronics--all possible points of failure. Buying a fuel injected bike I'm buying an electronic wonder, not merely changing out the fuel delivery system.

I've got another bike with fuel injection (DL650). It's worked well for me, but in general so has my carburated KLR. The latter is comprehensible to me (mostly), while the former consists largely of mysterious sensors, processors, and wee little wires. Maybe I prefer the carburated bike for the same reason I prefer map-and-compass navigation to the GPS, and the soundtrack provided by landscapes themselves to my left-at-home MP3 player.

Of course I also miss points and condensers, but that doesn't mean I'd return to them voluntarily.

Mark

Sounds like you don't prefer it for the same reason Ted doesn't. Most people that grew up with engines didn't grow up with multi meters and a soldering iron. FI is as old as the hills and with the 5 or so sensors needed plus a constant power delivery on the older models (new models can be batteryless so the kick starter is back in vogue) and a constant fuel delivery at pressure (wouldn't call it high personally) is about it. The amount of moving parts is less and to me this is always a benefit leading to more robust systems in just about all engineering disciplines. Only problem is relying on the sensor technology, but I reckon this is proven to be a moo point. FI systems provide a 'get home' setting which isn't providing you with the performance that sensor read outs would, but it still goes. A dodgy carb stops you in your tracks. Fuel pumps are everywhere and with a bit of old fashioned ingenuity you can make something work. The screens are cleanable.

I know of a lot of people take way to many spares, but I haven't heard of anyone taking a spare pump. Or sensors (I bring an oil pressure sensor because of oil leaks). All I bring is some extra wire, connectors and battery powered soldering iron which usually gets some laughs. Only had to use it on my own electrical work. Having not grown up with engines I've learnt about electricity before the workings of 4 strokes. So am more comfortable working with Ohm's law than the laws of dynamics (probably not the proper terminology but than again I'm not a native speaker either beer ). Less dirty work also.

Just about all bikes will stop running if the battery dies ,unless they have a permanent magnet alternator or use a magneto to provide the sparks .

They are many negatives to FI and the one that bugs me the most is the mapping ,try riding a Vstrom across a muddy field and you'll see what I mean ,the power comes on abruptly and is a bit like an on/off switch ,it's landed me on my arse a few times .It's fine on the tarmac but you can't feather the power in like a carbed bike .

Most people on this forum are travellers rather than mechanics and for them the best bet is to take a new or fairly recent bike and rely on the FI system [ there aren't many carburetted bikes available new these days].
And that's probably a goood thing because they shouldn't be messing with crap they don't understand ,Hells' teeth, most of the people who write ride reports are astonished when chains and sprockets wear out !doh


But for the old guard who insist on riding 20+ year old bikes ,well ,they'll have to put up with carbs for the most part anyway ,and they'll most likely love every minute of it .:mchappy:

Carbs at altitude
 

I can't add much to the debate about carbs and FI but I can respond directly to Uhuru's question.

I ride a 2008 DR 650 with a stock carburetor. I live and ride where you do in Colorado over high passes. I also have traveled on it in Mexico, and Central Asia. The stock carb runs fine without rejetting from sea level to 14000 feet. The bike makes about 35 hp so it is probably a bit slower than your F650 which I believe produces about 50 hp.

The DR650 is lighter and more agile, I think, and also quite tolerable on the highway. I've had no problems with mine (37,000 miles now) and trust it to go anywhere. It will, BTW, start and run with a dead battery.

The DR would be my choice, obviously, but I ride with guy who has a Dakar which has served him faithfully as well.

..................shu

I just added a 650 V-Strom to my "fleet"..

I bought it as it was FI and people talked about great MPG's.

On a good run, It can do 250-280 miles from its 22L tank which is about the same as my Africa Twin was with its 750cc 20 year old design. (although, the AT was thirstier in town)

It's also got that twitchy on/off power delivery like most FI bikes which I also refuse to spend £250 on a powercommander to fix.


FI bikes are VERY reliable as long as they're not B*W's/Aprillia with their dodgy fuel pumps..:rolleyes2:

Then again, the Africa Twins have even worse fuel pumps although it's an easy fix..

As a committed Linux user I adhere to the principals of “open source” and having control over all things software related and at the heart of FI is a computer and software. This makes FI bikes (and cars) problematic for me as their boxes are for the most part sealed and you are denied the ability to take control of the software that controls them.

Of course there is software that can give you control over (some of) your ECU's but as has been said by other posters, you are still constrained by the sensor suite the manufacturer has furnished your engine with. My biggest bugbear with ALL manufacturers is the narrow band lambda sensors they use when for a few pennies more they could fit wideband sensors that can transform the feel of an engine and give you infinite control over your fuelling. Without this simple feature you will never have decent fuelling on a FI bike as they are all now designed to conform to emissions regulations which in turn means the OEM's tune them to stoich and only stoich.

If manufacturers read these sites and in the unlikely event any of them wanted to build a serious RTW bike then they would sell the option of wideband sensors (one for each cylinder) and an interface to a computer with open source software.

Until that happens (as if!) junk the OEM ECU, junk the OEM lambda sensors and fit a megasquirt/microsquirt ECU together with some quality Bosch Wide-Band Lambda Sensors (LSU4) and with the free open source software take control of your bike back from the manufacturers, dealers and EU bureaucrats and tune it in whatever way you wish.

As Magnon said the components that make up an ECU are ridiculously cheap, in having a megatune made for you you can specify redundancy and ruggedised parts and multiple fail over features mean that if you have sensor failure the system still works. You can tune for any power, fuel quality or economy characteristics you desire for each gear sometimes (22:1 lean in top gear – lol) and have multiple maps you can switch to on the fly.

Megasquiting compels you to have a thorough understanding of your bikes ignition/injection, It's sometimes a steep learning curve and not for everyone but if you get into megasquirt beware, it is addictive but equally rewarding – how many KTM riders know that the rear cylinder is tuned differently to the front cylinder? Power Commander? - do me a favour! Lol.

I´ve owned a total five(!) AT´s in the past, one 650 and four 750´s, and now I´m on my 2nd DL650... and there´s a notable improvement in fuel economy. Might not be so apparent if riding slowly, but more speed & load on board, then it becomes obvious. If both are in standard form, the Honda is way more thirsty (not the only carb´d Honda to have this problem, check out XL650/XL1000) - I still love the AT, though!

DL650´s throttle response can be fixed, or at least made way better, in less than 5 minutes, and no need to install a Power Commander.

I'd like to hear more about this. Instructions, links, references....? Coaxing my DL along at low speeds is distinctly unpleasant.

Thanks.

Mark

It´ll need a little (2-3%) more gas at low revs with partial throttle openings. This is performed with SDS software (with a laptop, that´ll be connected to the bike to reprogram the ECU). And there should be other softwares that are capable of doing this, too, but I don´t know if these are widely available (SDS probably not, because it´s a tool that Suzuki dealers&workshops use).

You need the magic GIANT mobile phone looking diagnostic device and all the secret and impossible to get hold of fittings too...

The dealers don't like to share..... Most of them don't even know how to use it so don't buy it even !!

If you know another way, do tell....... ;)

Interesting. The local dealer denied there was any sort of problem and I was too disgusted with the rest of our interaction to argue. I'm not really interested in going back there, but if it would help me maneuver at slow speeds I'd try to muster the energy to do so.

Now, what was that about the advantages and ease-of-use of EFI? I was just out riding my carburated KLR today: 94,200 miles (that's 155,000 km) without a rebuild, a carb rebuild, or even replacing the fuel lines. The bike has run on all sorts of weird gasoline formulations on five continents, and it's been over 15,500 feet in the Andes (with stock jetting and no other mods). I added a filter in-line at about 50,000 miles, and I think I might have changed it once since then. I did break a choke cable once in Guatemala, and I've had water in the carb quite a few times. I had some episodes of what might have been vapor lock way back whenever-it-was.

But how foolproof is EFI during its first 94,000 miles? Do injectors ever get clogged? Do the little wiggly parts ever get worn and need replacing? Do fuel pumps last forever? (rhetorical questions)

Mark

I can't answer for bikes, but you won't find a truck or taxi runing carbs anywhere outside Africa or a few really backwards bits of the US. This is seventy year old technology (the injection bit) with stone age (1980's) electrics. There are plenty of million mile EFI vehicles out there. Only KTM and Rotax could actually manage to stuff it up!

Andy

The thing is I see efi engine management as ignition. and I cant get my head around the fantastic cost of repairing an ignition fault on a modern vehicle.

I recently had a big end fail on my Enfield. the cost of having it replaced ( with a better one and better crank) as a drive in drive out deal from a dealer was about a third of the cost of an ignition fault on my Volvo.

this means an ignition fault is now far worse than having a crankshaft fail.

It does not make sense to me. Although it does really as although the cost of producing unrepairable electronics is very cheap buying those parts isn't. It is simply a cash cow for vehicle manufacturers. for example the old bean can sensor on BMW's, use to fail. it was £90 odd to get a replacement from BMW, £ 3.50 from specialist electronic component distributor. Trouble is the manufacturers either source obscure parts or encase the lot in plastic so you cant get at it.

Threewheel, in an earlier posting here you said that if you take a cv carb to bits you will see a dozen or so moving parts. This is precisely the point. You can see and bodge manufacture mechanical parts. you wont get your local garage fabricating a microprocessor, even all it does is time the advance on the ignition curve, but you will be able to bodge a little auto advance spring to get you home.
I have been riding since 1961 and I have NEVER been inconvenienced by carburettor problems. I will admit to having changed throttle cables when on an annual service they have seemed to be worn. I did once have a clutch cable fail , Friday evening where the then A11 now M11 joins the North Circular, but was able to ride clutchless back to Cornwall.
I just never even consider a carb might fail. ( other than with cv carbs I might carry a spare diaphragm, but it is better to have a good one in the carb than ageing in your spars pack.

How many ECU's have failed vs CDI's? The point made and ignored was that you don't NEED all the sensors. How many pumps have failed (besides the KTM ones who don't seem to understand FI)? Most people wouldn't know how to repair a carby either. I know I wouldn't be able to, but I'm pretty confident fault finding an FI ignition issue with a diagram and MM.

The problem with FI is that when it does go wrong (which is very rare), it's a total pain in the ass to fix..

Most of the electronics are encased, hidden and it usually always takes quite a bit of dis-assembly to diagnose.


Bare in mind that although a FI bike might not "need" all it's sensors, many are hard wired to shut down if they lose a sensor due to safety reason, law suits etc. Some bikes will hobble home with almost nothing working though. It really does depend on the bike..

Fuel pumps do fail on FI bikes (Aprilias and BMW's are bad for this) and yes you are stuffed without them.. It's a simple thing to replace though and many a carbed bike has a fuel pump and they fail too.

Injectors can clog up but there is always a decent filter in most bikes.

Any workshop, who have decent knowledge of FI, and tools to work with Suzuki, should be able to make those adjustments. I´m no expert in that area, but it certainly did not look very complicated, and as I said it only took a few minutes. But the quality of the workshops, as well as their understanding about FI certainly varies (a lot!)

One correction: I just happened to meet the guy, who did the adjustments for my bikes (but this was a couple years back, so I´d already forgotten).. anyway, he said that he does not use SDS for other than fault diagnostics, and uses a different software for FI tuning (his was provided by Pro-Bike, but there are probably many alternatives - and I would not be surprised, if some are publicly available). And this does not require a specific "tester", that´d cost a fortune.

EFI - you've got to be kidding !
 

Deliberately provocative but VERY tongue-in-cheek subject line . . .

I'm stuck in Seoul awaiting a bike from the US that was meant to go on to UB but can't do to some air embargo so hunting for ways to Vladivostok. Currently building a row boat with a EFI outboard motor. :)

My KTM is an '06 and has a carburetor. The OEM fuel pump is rubbish and has long ago been replaced. It runs wonderfully with excellent throttle control and much better mileage (economy) than any FI Adventure's I'm familiar with. My "little" 530 EXC also has a carburetor. Both bikes have been re-jetted. The 530 would barely idle in it's "emissions approved" state.

The real question is silly - FI all the way. Uh, IF the FI is modern (it's not terribly modern on the LC8 (twin) KTM's. But if the FI is "modern" (like on many, many motorcycles, european and asian) - FI all the way.

I have these "flex jets" for managing my idle mixture screws (IMS) for jaunts between sea level and . . . 15,000'. FI doesn't need it. And yes, you can run carbed bikes over wide altitude ranges without adjustment but those tend to be the "beast of burden" engines, not anything with remotely "modern" performance.

As for the fuel contamination issues of FI. Well, change the filters regularly AND, more importantly, use a PUMP filter to winnow out dust and water at ingress, not egress, of the fuel tank. I have one that folds up into a very small bag that I use on my carbureted KTM when traveling far from home and/or in areas of variable fuel quality.

Yes, I CAN drain, clean, and re-jet my carbs in low light with very few tools. But who wants to ? Furthermore, FI gives you good throttle performance, good economy, adaptability to changing humidity and barometric conditions, high engine performance AND lower emissions.

Why hold onto an old technology whose "theory of operation" is rather unsightly ?

Kurt

Because it works. How old is the technology of the stone hand axe? Have you never struck something with a stone or half brick?

On my 2,500 mile trip to Poland I averaged 96mpg which is about what I normally get ever since I had it, including short runs to the shops. Using a carbed 500cc bike.
That is good enough for me.

Once you chopped up your fire wood with a stone hand axe do you use a flint and tinder to light it? Than sit near it under the bear skin tarp?
:Beach:

Did these arguments about old and new went on with CDI's became common place as well? I don't go back that far, but when I was intoduced to CDI's I was told to take a spare.

Back in the upper jurassic period I was trained to find ABS faults with a pin out box and a multimeter. The pin out box made life a whole lot easier as the ECU had 54 pins on one plug, so counting 9 pins from the left on the middle row and holding the probe on that pin while crouching in the footwell wasn't fun. Most dealerships however wouldn't buy one as they could diagnose a basic air system with an adjustable spanner and a pack of woodbines. The few who bought the pin out box and stopped thinking of the ECU as some mystic alien with superpowers then became seriously annoying as they made money from the shamanistic expulsion of electronic bogey men from trucks. Me telling some prat of a workshop manager that I'd driven 200 miles to pull off the connectors where he'd wired a mobile phone into the ABS modulator wires instead of power and earth only made them think of me as a super priest sent to expell the false prophets who'd been swapping ECU's for a month.

Ten years later the dinosaurs are extinct and every dealership has a laptop. They didn't spend days dancing round the truck wearing wet leaves and carrying a dead chicken, they plugged in and were told which wire was shorted in five minutes.

Five years after that you can buy a OBD2 reader in Argos (like Walmart) and do it at home.

Give it another five years and Touratech will sell you one built into a GPS and phone.

If you like hot bulb ignition and acetylene lamps go for it, otherwise it's just machinery that needs the right tools and knowledge. The fact that it's better machinery is why they call it progress. Find me a truck with drum brakes and a carbed petrol engine and I'll show you a haulage company not making any money (or a weekend play thing).

Andy

Going back to my 'electronics cost nothing' theory, it comes down to the manufacturers having the will to produce some electronics with built in redundancy, fail safe modes (bypassing faulty sensors, for example) and diagnostics which will ensure that the ECU itself is not the cause of a roadside failure. You will still have to carry a replacement fuel pump and possibly essential sensors that can't be bypassed by the electronics in a fail safe situation.

Of course, the manufacturers have no desire to do this as FI bikes are selling well enough and in general are incredibly reliable.

Overall I don't think there can be any argument that FI is much better than a carburator in most situations. However, if you are considering which is better for a travel bike where you may be in very remote locations, and even further from an equipped service centre, it would be interesting to know how many bikes have suffered a terminal failure due to FI or a carb - I'm guessing, but don't think anyone will have had to put their bike on a truck to the nearest town due to a faulty carb!

Sad to say I would have to tow mine. Wouldn't even know where to begin. Even though I understand the principles of the workings.

I did not say not to use any technology, just dont throw away things that work. As for careers I spent 1969 till my retirement servicing computers. By that I mean mainframes, not pc's although I did build my own PC in 1979 and wrote my own bios and operating system for it. This was in the days when computers did as they were told and you did not need a lawyer around to negotiate removing a file. As for using old technology, how old do you think screw threads are ? No doubt when the manufacturers start to spot weld your engine together to make it user tamper proof to comply with Euro6 emissions you will herald it as a great achievement now you don't have screws coming loose.

Do you own a multimeter and a wiring diagram?

If I had a tenner for every electronic vehicle system I'd been to see to replaced chafed wires of blown fuses, my choice of motorcycles might be extended beyond 10 year old Triumphs.

Andy

Yep, but that comment was on fixing carbies not electrical. Got just about all the documentation known on that bike and with today's smart phones there is no excuse for not having it on ya. Take a soldering iron on my FI bike as well. It's about as important as vice grips now. I know which I used more often. Due to my own accessory harness though. No failing of the OEM wiring, but I bought the thing new. And the BM wiring hardware is pretty good with high quality wiring and insulation and Tyco gear. Their routing is another story, but I've modified the bike so much that I've solved that.

When I started trail riding with the old fella's here I was a complete noob and kept getting told to "be prepared" over and over. So since I worked out for myself what to take at all times and how to minimise it. So last time I went out with one we had a flat and between myself and another fella who got told the same thing we pulled out all the toys available. Should have seen the look on his face. Had the thing back on the tracks in record time. :offtopic:

Problem solved
 

In case anyone is curious, I sold my efi 2005 BMW Dakar and bought a 1983 BMW R80ST, and really haven't looked back. I love the airhead's much lower C of G. This is a far better handling bike for Colorado mountain roads than the Dakar. Best of all, there just wasn't a noticeable problem with high mountain passes despite going from efi to carbs. I do miss the Dakar's 60mpg, though--the airhead is only good for about 40mpg.
Thanks for everyone's input--most helpful.