Raptor 660 cutting out on high revs

[mwilliamson]

I have an '05 raptor 660 purchased a year ago that my girl rides. Over the winter i had a yamaha dealer install a gytr jet kit, cdi box. I also installed a k&n filter, and d&g exahaust all around the same time.

Now it seems that when i hit around 5 grand the rev limiter kicks in??? sounds like it? The box does not have and adjustible rev limit.

It has great power up until it starts cutting out. I pulled the spark plug, looks normal, replaced it anyways. Filter is clean. Don't know where to go from here!!!!!! It didn't do this before the "upgrades".

ANY IDEAS ?????

[outlander560]

wen u had the shop install the jet kit was it before or after u put the exhaust and filter on?

[Stoopidbot1]

Do you have your stock CDI? Put it in and try. CDI's are a part that fails often.(after market)

[DirtDemon]

True, Ignition components can be troublesome. It does sound like the CDI is likely the problem. You may also want to check the timing, sometimes it can be thrown off with a change in ignition components. Outlander also has a good point, if you changed the pipe and intake after it was re-jettet, and you didn't re-jet yourself, then you may just need to re-jet again. Most performance upgrgrades will require re-jetting.

[mwilliamson]

Thank you guys so much!!! The pipe was installed before the rest of the work was done. The filter, cdi, and rejet were done by the shop so I would hope that it was done in right order. I will check the timing then go to the box. Any suggestions on a good cdi box because i suspect that it will not warrantied with it being six months old. And of course i left the old cdi with the shop.

Thanks again!!!

[Stoopidbot1]

There are actually only 2 different kinds of CDI boxes. There is the Dynatech style which is what Big Gun uses. Big Gun Rev Box Yamaha Raptor YFM 50 MINI ATV:eBay Motors (item 330333968362 end time Jun-27-09 11:06:04 PDT)

In the UTV world the Dynatechs have about a 25% fail rate. Most companies use a Dynatech box with their own sticker on it If you do replace it go with a Big Gun Rev Box.

MSD makes the best CDI box out. I'm not sure if they have a model for the Raptor.

Edited June 16, 2009 by Stoopidbot1

[mwilliamson]

any ideas how to check the cdi? i dont have the old one. Any ideas where to get a good deal on a stock cdi

[Stoopidbot1]

As far as I know there is no way to test a CDI other than putting a different CDI in the machine and see if the problem is fixed. Here is a start for your look. 02-05 Raptor 660 share the same CDI

[mwilliamson]

I have a real good feeling that the cdi is the problem. I actually got the manufacturer

(ricks motosport elec.) to warranty it by going around the dealer in town and the supplier they got it from and contacting them direct. They where real nice and understanding. I will see in about a week if that will fix the problem.

Thanks for everyones input and help with this issue!!!!!!

[Stoopidbot1]

Any company that sells a CDI knows that them being bad is not out of the ordinary. I'm glad to hear that they are working with you.

[DirtDemon]

Good luck, please let us know what happens.

[Stoopidbot1]

The CDI that you got is a Dynatek. The other company you bought it from just puts their sticker on it. When the Dynateks work, they work great. But like stated before, in the UTV world they have about a 25% fail rate. And the ones that fail, do it instantly. It never works right.

[Sc0tt]

25% that sux. Failure is not an option...

[Stoopidbot1]

That's why I run MSD

[DirtDemon]

MSD has been making quality ignition components for all types of vehicles for thousands of years. The only way to go for an aftermarket ignition system IMO.

[mwilliamson]

Well the new cdi didnt fix it, still cuts out around 5 or 6 grand. I noticed it sputters a little while accelerating too. Im going to check the timing. How about the valves? Clearence off, bent valve, etc.??

Or does anyone think the shop jetted it wrong? I have not ever jetted before, my lack of time and experience was why they did it in the first place. Or should i just take it to a shop and save myself the hassel??

[ATVmechanic]

Well the new cdi didnt fix it, still cuts out around 5 or 6 grand. I noticed it sputters a little while accelerating too. Im going to check the timing. How about the valves? Clearence off, bent valve, etc.??

Or does anyone think the shop jetted it wrong? I have not ever jetted before, my lack of time and experience was why they did it in the first place. Or should i just take it to a shop and save myself the hassel??

Take it back to the shop, it does sound like they jetted it wrong, on high rev you're most likely fuel starved.

[DirtDemon]

I would check the timing and valve clearances before I take it back to the shop just to make sure. If those are ok, then I would look to the jetting, and there I would agree with ATV mech in that it sounds fuel starved, meaning that you would need to go to a bigger main jet. Weather or not you want to bother with taking it to the shop or not is up to you, personally, I would choose to deal with it myself, jetting is easy enough, but some people don't like to deal with it so...