Horizons Unlimited - The HUBB - XT600e 2002 heavy misfire/bogging

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Quote:

Originally Posted by Beezageeza (Post 557383)

Sounds to me like you have checked out the problem in a logical way. First, carb and fuel/air supply. At one point even changing the carb completely only to be left with the same problem. If it was air/fuel supply, the symptoms would have changed measurably even if the problem remained. So, assume it is NOT the carb...

Next logical thing to troubleshoot is the electrical system. You replaced the coil, reg/rect, spark plug, leads and pretty much everything else in the ignition system. This also made no difference at all.

As the problem occurs in the rev range when ignition advances, anything that controls advance could be the culprit.- TCI and also the sensor in the front of the stator. Many TCI/CDI systems have 2 circuits (one for retard and one for advance) rather than an actual curve, so there is one possibility (dead advance circuit in TCI or the sensor which is part of the stator). Me - I'm too dumb to bench test a TCI so replacing it with a known working unit is the best option.

A left field suggestion...
1. a rat may have crawled up the exhaust pipe and died. It's amazing how much crap a family of rodents can pack into an exhaust pipe. This will have the effect of reducing the amount of exhaust gases that can leave the system and has a similar effect to limiting the air inlet. This happened to me when I restored an old Yamaha XS750 (with straight-through pipes). Had me absolutely stumped why the bike would not run. Took of the pipes and extracted about 10 litres of "rat house" from the straight-through pipes. After that the bike ran flawlessly.

Wow thanks for the compliment, I feel all clever hahahah...
Anyway I did the final test today with another pair of carbs, same problem...
So as the process of elimination, it must be the TCI, since the pickup coil seems within spec...
I'll order another TCI after the carbs have been returned.

Also an interesting test I did, after the comment on having the wires for the ignition coil the opposite way around.
As it turns out, for me at least, no matter which way I switch the wires on the ignition coil, I'll always get good spark hahahah, don't ask me why that is or if it will do something to do coil, idk :innocent:

I hope you can entertain the rantings of an old grumpy rider. First, check the pipes. This is cheap. Bite me, I'm dutch, and do not like to spend money...

THEN try with a working TCI (better if you can borrow one but you might have to buy).

THEN, think about the stator assembly and try another one.

You will notice I have ordered my diagnostics according to cost. Refer to my initial statement...

Aloha and enjoy the journey

Quote:

Originally Posted by Beezageeza (Post 557457)

Sorry, I forgot to mention, I have actually had the pipes off multiple times. I'm a 100% certain they are clear, I've had all the sections off too and its an aftermarket exhaust too. I had to weld extensions to the engine studs so I can mount the pipes properly. I couldn't get the studs out because my welding skills are not great, but I did manage to secure the pipes on good. They've been on there for the last 7000 miles ^^
Also the bike hasn't been sitting around at all since I got it. I use it as my daily since I don't have a car or another motorcycle.

Does the ECU/TCI for a 3TB model match the 4PT advance curve ? Can you swap the TCIs from the years between 1990-2002 ?
Anyone done that before :?

For instance this one claims to do it all, unless I'm misinterpreting it? http://www.electrostator.com/fr/xt60...re-xt600e.html

Can you use a CDI instead of a TCI ?

I got a hold of a timing light....anyone know how to use it for the XT600 to confirm the TCI?

I figured that if it is the tci then the timing light will not operate as usual when it reaches that rpm range and there will be a difference in the strobe pattern ?

the xt's flywheel has only a mark for idle advance, so even if you manged to see it through the tiny M8 hole while pointing a strobe, it will not tell you anything about the advance curve.

so you need a timing/degree wheel too and attaching it to the crank is not that easy on an xt.... done it to adjust my supermono road racer ignition, but it involved turning an adaptor instead of the flywheel nut, plus some sort of sealing of the oil splashing behind the cover.

but that was worth doing in a very highly tuned motor. the stock TCI ignitions are so reliable that you never need to really check timing with a strobe, even less so the advance curve. personally i think that you are barking under the wrong tree.

AFAIK all the TCI's for 1990 and up xt's, including the carb'ed 660's will work. CDI's are a totally different principle, need different flywheel/stator

Quote:

Originally Posted by turboguzzi (Post 557536)

Thanks for your response! I'll try using the light today and see if that confirms my assumptions.
A few people mentioned marking up the wheel from the Tenere forum, I'll take the side cover off today and visually inspect the stator/pickup assembly too.
I honestly do not know what to think anymore, I mean 3 different carburetors and the same problem persists, so its either the pickup coil or the TCI as far as I understand?