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Discussion Starter · #1 ·
Hi all,

I'm stuck again. The starting problem is back after 3 faultless races since a rebuild. Usual long winded story, so bare with me please!

1. Had engine rebuilt and reinstalled ourselves. Starter would turn but wouldn't start the engine - no spark. Checked HT leads, coil, spark plug etc. Only change (aside from the rebuild) was taking up some of the slack on the throttle cable on the carb. Twisted the cable at the thumb throttle end the next day after some advice and it started lovely.
2. 3 races, lovely, but on the last race towards the end the throttle kept sticking open when the bars were turned. Then it kept cutting out instead of idling regardless of where the bars were. Quad went in garage in disgust.
3. Pulled quad out to get sort it out and it wouldn't fire up. Charged the battery, still wouldn't fire. You can hear the starter turning but it sounds like no spark (which is the noise I heard at step 1).
4. Tried putting on a dirtbike CDI but that didn't work (mind you, didn't do anything to any of the cables that come off the carb).
5. Fiddled with the throttle cable and the idle screw and after a full charge it just starts, runs like a bag of hammers but will not idle.

So these are the thoughts: :confused:
1. Dirty carb due to crack in air intake boot (have not checked this yet)
2. Issue with TPS or is it the TORS?
3. Poorly battery.

You lot have been superb so I'd really appreciate any help as I've run out of hair to pull out!!!!! :( :wacko: :mad:
Thanks in advance as I'm feeling quite depressed! :(
 

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Slide height idle screw setting to high - black knob on side of carb body, if the slide height is to high it triggers the TORS and no spark...... Lower slide height via black screw and reset idle mix to give nice idle speed.

Make sure there is slack in throttle cable

You are right on the edge of the tors cutoff setting hence why it is picky.....
 

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start with that, but if by a bag of hammers your mean loud and obnoxious inside, check your valves and change your oil and see what comes out... but starting problem is most likely tors. and bike cdi will eliminate tors, do make sure you got the right one?
 

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Does sound like you are on the right track of diagnosing your problem, when my boot cracked it would take a full battery then a recharge to start it, but once it started it seem to run fine. After fighting it for 2 weekends I finally had enough and did everything but check the boot because at first glance it looked good but after valves were fine, good spark, and plenty of fuel I finally took the boot off to find there was definately a crack in it and after replacing it have yet to have another starting problem.
 

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Discussion Starter · #5 ·
Hey folks,

Thanks for the heads up.

Stripped everything down so the quad now looks a bit sorry for itself. On the upside, found the Carb/Engine intake boot to the engine was cracked. Ordered up a new part so just waiting for that to arrive (unfortunately I didn't order the updated boot as I only read this after I'd ordered it, but I've got a spare coming in so I now know to check and replace more frequently. A good friend of mine who knows these motors well is cleaning the carb (if I did it I'd end up with a whole pile of bits left over!!). Also gave me chance to give everything a spring clean too :)

I'm hoping it's the carb boot causing the issue and nothing electronic or even the throttle cable. Will update when I've got my bits and it's back together.
 

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Discussion Starter · #8 ·
Yep they do - there's a sticky note above this one. Here's the part numbers from it:

Left is new one (59436044200), Right is the old one (59436044100)

would appear the same boot clamps are used -100 and -200 setups
 

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Discussion Starter · #9 ·
Right, it fires up and runs lovely with the new intake boot but won't idle - any ideas?
 

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Discussion Starter · #10 ·
FINAL UPDATE.
She runs sweeeet. Had a little tweak to the position of the TPS and some fiddly fiddling of the idle and she runs. TPS and TORS - you're history!!!
 
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