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Discussion Starter · #1 ·
i changed the head gasket, jetting the carbs to stage one, de-baffled the exhaust, and replaced a few bolts in the motor. A few months ago after I jetted the bike it wouldn't run propperly it was sputtering shutting off at low rpm and couldn't go over 100 kms an hr without feeling like I was hitting the rev limiter. I Synced the carbs and the problem was resolved. Now four months later the symptoms have returned except at a lower speed of 50 km per hour and up it feels like, sounds like, and acts like a rev limiter is happening. So I re synced the carbs, and ther was no difference. After a long while of frustration I took it into a mechanic shop ( st onge recreation) where they assumed it was the battery, that was replaced. Then they thought the fuel pump was the problem. Still nothing so they cleaned my carbs removed my jets and re-synced my carbs.. In total they took 600 dollars and three weeks of my time and it came back in the same condition. any Ideas?
 

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AS christikitti said and also this stage one jetting kit, did you buy it off the shelf as a kit? as ive heard nothing but bad news about them. as they dont know what you've actually done to your bike. they are for a sterotypical upgrade. you should always to be safe work out your jetting yourself ( or get someone else who knows how to). spluttering can be a sign of too much fuel enter the cumbustion chamber and not burning. so you may just need to adjust your air/fuel ratio. if you get really stuck i can ask around the workshop for you as i dont normally deal with these things unless its my bike!
 

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oh and another thing does this problem come and goe to an extent or made worse by anything? as ive had a similar kind of problem and it was corroded spark plugs not firing which made it feel teh same as just before your bike dies from runing out of fuel.
 

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Discussion Starter · #6 ·
If i lift the back of the bike off the ground i can easily exceed 200 kilometres per hour but if i take it out for a test ride it is hard to get it to go 80 kilometres per hour before it starts shaking and jolting.. but the bike has all kinds of power in first gear right into the beginning of second.
 

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AS christikitti said and also this stage one jetting kit, did you buy it off the shelf as a kit? as ive heard nothing but bad news about them. as they dont know what you've actually done to your bike. they are for a sterotypical upgrade. you should always to be safe work out your jetting yourself ( or get someone else who knows how to). spluttering can be a sign of too much fuel enter the cumbustion chamber and not burning. so you may just need to adjust your air/fuel ratio. if you get really stuck i can ask around the workshop for you as i dont normally deal with these things unless its my bike!
Off the shelf jet kits work fine if you actually need them. The problem is that people think jet kits are power adders, and treat them as such. I know plenty of people that take totally stock bikes and throw jet kits in and cant figure out why they run like shit. With aftermarket exhaust and a K&N my dynojet kit is pretty damn close to perfect.

If he has stock exhaust, and a stock air filter, then you probably do not need a jet kit - even though you removed or punched out some baffles.
 

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And that shop you took it to is full of idiots. You should always diagnose a problem before replacing parts. Sounds to me like they never even bothered to TEST the fuel pump, or anything else, before they just threw YOUR money at it. Never go back to them if you ask me.
 

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Discussion Starter · #9 ·
i have no intension on going back to that shop.. but i put my jets back to stock and still no real difference.. now during the test ride it can almost reach 100kph that is the only difference.
 

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Sounds like a fuel starvation problem. Under load, you use more fuel than just lifting the rear wheel. I would start with checking fuel pressures and volume. Make sure you don't have any partial kinked fuel lines or fuel lines that are old and swollen, as they plug up inside.
 

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Next thing to do is what I did and get an O2 bung installed and monitor AF ratios via gauge. It's helped me out tons! I now have a near perfect idle and even better cruise.
 

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Discussion Starter · #13 ·
I have been contemplating that for a while.. Did your weld bungs in your individual exhausts and tune each cylinder individually or a single bung after the exhausts meet and turn each pilot screw out equally? and what kind of O2 monitor did you use?
 

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I used a single bung in the collector, and just stuck some cheap narrowband gauge on my bike. I use a laser temp sensor gun to adjust my pilots via header pipe temps. My pilots are flat rich right now, but everything else seems good till I cruise for a few miles at 80 in 6th gear. Then if I romp on the throttle with a downshift, It acts like it's running out of fuel. Still figuring that one out.
 

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Discussion Starter · #15 ·
I fixed the problem today. I re-build the carbs,changed the fuel mixture to dead stock, and replaced the battery because it was registering a little low, also ran over all my vacum houses for good measure and made sure my ram air vacum hoses weren't clogged, disconnected, or cracked i had to replace one that was so damaged it wouldn't stay connected.

Thanks to everyone for there help
 
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