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Discussion Starter #1
I originally thought this was a jetting issue because of the big bore/intake/exhaust mods but after going through jetting of 135-165 mains with no difference in the mid to top end I'm starting to think I have a different issue. Below is a link to clip I took of it. Mid to top of throttle is just acts like the revs hit a wall. I only get good acceleration up to 40%

Clip of issue
 

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Master of the Electron
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Did it ever run correctly for you? What have you done to it since?

What, exactly, ARE your mods? Are you running aftermarket needles?
 

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Discussion Starter #3 (Edited)
It didn't run when I got it.
It has 686 big bore
Big gun slip on exhaust
K&n filter
Parking brake delete
Lid was cut, tried running with it like that, with cuts covered, and with no lid

Since I got it I have replaced
Timing chain (was stretched)
Head and base gaskets
Cleaned tank and peacock
New fuel filter
New fuel lines
Fresh fluids
Set proper valve clearance

I tried jetting it with stock needles
Started with the stock 22.5 pilots 140/145 mains 2.5 turns out middle clip
Went all the way up to 27.5 pilots and 165/170 mains
Still had the same issue
I have recently tried a set of after market needles I have with a more steady taper then the stocks. Not name brand just came with one of the rebuild kits. Currently going thru all the jet sizes once again to try it but so far still stumped. Have noticed it goes rich on the plug much lower on mains with the aftermarket.
You had replied to my post on jetting and based on my 5300 ft elevation and 100 deg weather you stated I was close with the 155/160 mains
 

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Master of the Electron
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Thanks for the detailed explanation.

Have you had the emulsion tubes out? Occasionally they get re-installed backwards with symptoms similar to yours - the bevel should be up towards the needle. If you find them backwards, fix it then go back to the suggested jetting.

BTW, if your snorkel is modded or missing you need to jet richer than stock (for your elevation)
 

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Discussion Starter #5
I did rebuild the carbs and replaced the emulsion tubes. I will check those later today when I get a chance.

As far as the snorkel I'm unsure which part your referring to. I should note my right side intake (carb 2) joint is kinda shredded at both ends. I get it on with the clamps but I'm sure its not air tight. I havent been able to find a replacement that isn't a month out yet. Also I dont have the lid on.
 

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Master of the Electron
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If you have a vacuum leak at the carb - intake manifold boots you will NEVER get it to run right. If the leak is at the air cleaner - carb side it's not as important. Spray carb cleaner spray or starting fluid around the boots with it idling - if idle speeds up you have a leak that needs to be fixed.

Don't know how you're currently jetted, but if it is jetted for lid, your mid/top will be screwed with lid off... testing must be as riding.
 

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Discussion Starter #7
Thanks for the detailed explanation.

Have you had the emulsion tubes out? Occasionally they get re-installed backwards with symptoms similar to yours - the bevel should be up towards the needle. If you find them backwards, fix it then go back to the suggested jetting.

BTW, if your snorkel is modded or missing you need to jet richer than stock (for your elevation)

Which end is the bevel end?
I have it this way up
 

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Master of the Electron
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I think you are showing the bevel, but It's been a long time... I'd need to see both sides.
 

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Discussion Starter #10
If you have a vacuum leak at the carb - intake manifold boots you will NEVER get it to run right. If the leak is at the air cleaner - carb side it's not as important. Spray carb cleaner spray or starting fluid around the boots with it idling - if idle speeds up you have a leak that needs to be fixed.

Don't know how you're currently jetted, but if it is jetted for lid, your mid/top will be screwed with lid off... testing must be as riding.
I sprayed the intake boots from head to carb and had no changes in idle. The intake joint in referring to is the tube from carb to airbox on carb 2. Both ends are kinda shredded. I had a thought, the small tube that connects into the boot that goes to the diaphrams in the carb are not sealing very good either. Could this cause the needles not to fully lift?
 

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Discussion Starter #11
Ok so I wanted to report success! It turned out to be the Rev limiter. It dawned on me when I disconnected the reverse switch wire and DIDNT ground it and tried to run it the quad acted exactly the same. If it wasent the limiter I figured it would have gotten worse due to the limiter engaging. When I tried to pull the wire up and ground it on the battery it would just spark (maybe something in the wiring the PO did between the sensor and the cdi) so this caused me not peruse it farther. I decided to cut the green/white wire about 3 inches from the cdi and run a wire from the plug side to the negative terminal and BINGO she revs like a beast. I hope this helps others as they research their problem and I'll leave the videos up so they can compare symptoms.
I wanted to thank quad maniac for his responses in trying to figure this out.
 

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Master of the Electron
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Which rev limiter? Is your red stator wire disconnected? This is the only way the reverse RPM limit would be much above idle. The parking brake limiter is also very low RPM.

Good find!
 

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Discussion Starter #13
It was the reverse limiter since the wire I cut at the cdi box was green/white.
The cloth braided red wire coming from the stator is still plugged into the plastic connector so I'm not sure why I was able to go half throttle before it started hitting the limiter wall.
 

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Master of the Electron
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Strange, for sure. Do you have stock or aftermarket CDI? Stator?
 

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Discussion Starter #15
I'm pretty sure its a oem cdi box and I'm not 100% sure on the stator. You commented in my other thread about needing a ground to frame. Maybe that was why I was getting the limiter in the first place and why it let me go highet then idle?
 
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