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Discussion Starter · #1 ·
I have a 99 R6, and likely have a simple problem that I cant seem to crack. When I first tried to start it up this season, the starter wouldn't even turn, so I naturally assumed it was the battery (about that time). I bought a new Yuasa, slipped it in and now the starter turned, but the bike still wasnt starting. So...next came new spark plugs, gapped and installed them per the service manual, also cleaned and oiled the air filter while I had everything off, but I was still only able to get her running for about 5 minutes (and running really rough at that...backfires and smoke). Drained the tank and put in fresh fuel ( the old was treated with stabilizer, just wanted to be sure that that wasnt the problem), that made her run longer (and i thought i had it beat), but next thing I know, as soon as I give it any kind of throttle above 6k (after running happily for about 10 minutes), she bogs and then tries to die out. I think that i might have flooded the engine with fuel a little trying to get it to start (copious amounts of gas dripping out the bottom of the bike), so Im not sure if thats the problem. I only say that because every time I try to restart it, rather than the fuel pump just pumping a little (just a couple clicks like it usually does), I hear it run for about 5-6 secs straight. Naturally, after trying to get it started a couple of times, she floods, and here comes the gas all over the engine... As far as I can tell, no hoses are pinched, and the carbs dont appear to be clogged as when I got it running the last time, it was idling pretty smooth. I am all out of ideas and wondering if I should just break down and call my local dealer so they can have a go at it (which I cant really afford to do). Please any help or suggestions are appreciated.
 

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Sounds to me that if it will idle, but dies when you try to deliver more fuel to the carbs, it is either:
Clogged jets
Stuck float.

Clean your carbs, and check your jets for clogs.
 

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I second TexasR6, sounds like your carbs are just gunked up.

Let us know how it goes, there's nothing worse than an unfinished thread. :cheers
 

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Discussion Starter · #5 ·
Cleaned the floats (actually the float valves were all funky), so at least now it doesnt spill gas everywhere. I managed to start it up, but it sounded real deep (almost like a twin). Am I correct in assuming that this is a result of the jets being clogged too? Would that produce this kind of engine noise? Or is it just a case of the carbs being out of sync?
 

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I would clean the jets first. If it's only getting a little bit of fuel it will not run right. If that doesn't work I'm not sure. I wouldn't think the carbs would get out of sync just by sitting there.
 

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Discussion Starter · #8 ·
Thanks Loki, now you got me all paranoid. I just have changed the plugs and cleaned the carbs (actually will be re-jetting this weekend)...how would that mess up the timing? I havent done anything inside the engine itself, and from what I understand the maintenance that I have done so far shouldnt impact the timing. Is this incorrect?
 

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he was taking a shot at TXR6 would messed his engine up trying to play god.

you didn't mess with your timing at all.

keep us updated as to your progress!
 

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Discussion Starter · #11 ·
Rejetted over the weekend (Dynojet Stage 1), and it seems that that took care of the problem (at least nothing a good sync won't take care of). Thanks all for your help and suggestions. Round is on me if any of you make it to Chicago.
 

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No jet kit needed

I had those symptoms once. If you have all this going on AFTER you've cleaned your carbs and synced them, then...

If you have access to a temperature gun with the laser sight, point it at each exhaust tube off the block. Each one should be at about 190ºF-210ºF. If one is low (about 120ºF), then it's likely that a coil stick is bad.
 
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