Carbs To Injection
The Bing Carbs Can Be A Bit Fussy, And For That Reason I Was Thinking Is It Possible To Replace Them With The Oil Head Fuel Injection Set-up. I Beleive The Fuel Injection Automatically Compensates For Altitude.
Any Takers On This One........ |
Could be done but it won't be easy. You'll have to fit all the relevant sensors plus a fuel pump to the airhead to make it work. You'll then be faced with the task of remapping the oilhead injection to suit the airheads needs. Sensors include Lambda probe in the exhaust Y-piece, air mass & density plus mating the fuel pump (external) to the injection system. You may also need to fit the oilhead ignition system (Hall Sensor) to trigger the fuel pump & injection. The ignition will also need to be re-calibrated to take account of the airheads different ignition requirements i.e. advance curve & rev limiter etc. Making the oilhead wiring harness fit or making one from scratch won't be an easy task.
You'd be better off off using an aftermarket combined injection & ignition system that's programmeable from a laptop. Note that several oilhead owners have gone ditched the injection & reverted to carbs for simplicity. If you're running rich at altitude, it's easy to swap jets on an airhead...... |
I get your drift. I did not realise that some oil-heads have injection reliability problems.
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If I might add, it is not so much the injectors whose reliability is problematic but rather the associated components, specifically the fuel pump and the hall sensor.
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Yes.
Luftmeister used to have a kit. Call Chris at CC Racing, SJ BMW Racing , he might be able to help you out. It can be done and I have lately seen quite a few mentioning that it is more or less just to bolt on the oilhead kit. However... the airhead electrical capacity is not enough so one will have to enhance it... Either you do as I have done: http://www.webstruktur.com/svea/board/artik/bilgen.html SVEAs FRÅGOR&SVAR: Bilgenerator på MC Or you buy an aftermarket replacement kit: BMW Motorcycle Aftermarket Alternators Note: - study the charts! Please be aware that the airhead is mainly operated below 3000rpm and in city traffic is tends to be more around 2000rpm... compare this with the charts. My solution superceed this by far - I have 55-90A depending on installed alternator from the rev's I choose pulleys for. I have my bikes giving me full 70A (980W) at 1700rpm. The answer to your question is: YES! Counter question is: Why?... Any slide/throttle carbs is better than the Bing CV. I have Dell'orto PHM 40, but you should not get so large carbs. 800cc should have 34mm and 1000cc should have 36-38 (RT vs RS). It is possible to go 2mm up or down - it affects where the torque response comes and have some effects on full throttle; smaller will respond better at low revs and vice versa. Let us know how it goes for you with the conversion to fuelinjection! -:) |
Personally I like Bings and in many ways I find the superior to injection but Silent Hektik might fit your needs (if you have the cash): SILENT HEKTIK Automotive Hard- & Software - BMW Boxer ICM (Einspritzung) für Normal- + Doppelzündung
http://www.silent-hektik.com/Boxer_7.jpg When it comes to the discussion about the size of the throttlebodies I’m not sure if I agree with Lindberg, at least not when it comes to Bing. |
[quote=AliBaba;
When it comes to the discussion about the size of the throttlebodies I’m not sure if I agree with Lindberg, at least not when it comes to Bing. [/quote] :laugh: Alibaba - this IS a controversial issue -;) I know -:) As for carb-sizes; I base my point of view on two facts: a) I've tested b) It is the correct mathematical / physical / engine technical combination. You will find the formula in Graham A Bells Fourstroke Performance Tuning published by Haynes Books. Bells non-verified (no references) books claim is corroborated by the textbook in internal combustion engine fundamentals by Prof Heywood at MIT. So you have experience and scientific facts. However, in -real life- things are not necessarily the same as in theory of the abstract world... what works for you on your engines may or may not work on mine, and vice versa: and this I know for a "fact" as well through trial and error - my bikes/engines do not behave in the same manner in spite of being the same cc and series. We have to be open for tricks played on us by reality -;) Isn't great to be able to disagree -:) Thank you for the tip on the Silent Hektik injection kit! I have compleatly missed that they have it. Most greatful for the up-dating -:) |
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I know the theory, but I also do know that CV-carbs suffer less when “oversized” then most other carbs :mchappy: In fact I have built my recent engine with small carbs, but now I’m in doubt…. The engine is running well (80 N/m @ 3500 RPM, stock ignition) but I will like to achieve the same torque at a wider RPM-range. But of course I will do various modifications at the same time so even if I succeed it doesn’t prove a thing. :smartass: |
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It's interesting that some of the BMW Factory Dakar riders (Juan Rom and John Deacon) decided to go with the Bing carbs instead of fuel injection on their race bikes.
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I don’t think it was the rider’s choice to go with carbs. All the 900RR (including Lundmarks bike) was equipped with carbs.
The 900RR is a beautiful bike, it’s the only oilhead I would like to own: http://www.actiontouring.com/pic/900rr.jpg Later when the HP2 was used for racing they kept the FI, but it was a few years later and the HP2 was only used for shorter competitions. |
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The Lambda Probe failed on my girlfriends 1150GS at 50,000 miles but that's it. |
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Problem solved by replacing the injectionsystem with Bings. Think it was the 1995-96 issues that were the worst. The company back in 1997 that specialized in these conversions was: WITEC Motorsport One can drive many miles using carbs on the electrical power from the battery should the alternator stop working. One will not get far at all with a fuel injection vehicle... I would -never- go on a trip through desolate contryside using fuel injection if I could replace it with carbs. The alternator on the oilhead is a standard car-issue so it is far better than the stock airhead alternator, but still... I like to play it as safe as I can -;) |
How is it going?
What have you decided to do? |
Are you talking to me!!!!
Albert I fitted a pair of 34mm Mikunis. I had to change some of the jets as they came with standard jetting from the good ol USA.
Much more improved throttle response , and I think better fuel economy, regards Mike T. |
Hi
anyone knows where to get the flag stickers from? greetz |
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