Mongoose 90 cutting out

[cleanone]

We purchased a Mongoose 90 for my son last year, good bike, no major problems. I added an aftermarket pipe, and upped the main jet to a 108 then 110. Put some holes in the air box lid as wll. Alos, cut the light green wire on the CDI box to up the rev. limiter. the bike cuts out at wide open throttle, sputters and sounds like it is hitting the rev limiter or governor. Any help would be greatly appreciated.
Thanks, adrian

[badvox]

Sounds like at top end you have an air fuel problem.

Also, I dont think the green wire actually removes the limiter but just ups the limit. Not totally sure though. Once you are at top end and holding it there you may start to hear some belt noise like a whining sound.

You may wanna go for a sprocket change to get more top speed out of it before maxxing it out.

[cleanone]

Thanks for the info. I was just wondering if anyone else had any experience with these models and if they modded the engines. Any idea on where to get a larger front sprocket? I'd like to go one tooth to up the ratio, I guess I could try adjusting the air/fuel screw and see if that helps. I've added pipes/jets/air filters to several bikes and never had a problem like this, it didn't do it when the bike was stock.
thanks!

[dj250r]

badvox

you guys going to start racing the kymco mongoose?
Dwayne

[cleanone]

Hey badvox, that DTZ pipe on your Mongoose 90, it's "desert toyz" right? did you experience any cutting out when installed? How's the Powroll kit holding up and how's it run?
Thanks!

[badvox]

Originally posted by dj250r
badvox

you guys going to start racing the kymco mongoose?
Dwayne

Yes. Plan is to race it fairly stock for 2 rounds while we gather some parts. Then one day show up with it totally done.

My son has never raced so 2 rounds stock are definitely in order. He has been on a track and picked it up pretty quick so just needs that race condition added. As long as he comes off that track with a smile thats all I care about. If it becomes no fun having his booty handed to him then we move in with the mods.

Good Plan?

[badvox]

Originally posted by cleanone
Hey badvox, that DTZ pipe on your Mongoose 90, it's "desert toyz" right? did you experience any cutting out when installed? How's the Powroll kit holding up and how's it run?
Thanks!

Yes its a dezert toys pipe. And yes it had issues at first. We had to lean it out after flowing fuel to it. The carbs on these are not very good for performance so it took some tweaking. Well I mean once you add a pipe. They're made for scooters which means good gas mileage.

Lets face it they are not designed for performance at all.

Powroll kit is not installed yet see previous post. However I will tell you that Jesse Skvarek has placed first and second in the opening rounds of GNC this year. From what I know the motor has held up very well since first being built.

The crank in this quad is extremely strong.

[cleanone]

Hey badvox, one more question, on the carb there are two adjustment screws facing out at the upper portion of the carb when looking at it from the side (fuel petcock side) and one at the bottom, I know the one at the bottom is a drain but not sure which one of the two uppers is the air/fuel mixture screw.
Thanks!

[badvox]

Originally posted by cleanone
Hey badvox, one more question, on the carb there are two adjustment screws facing out at the upper portion of the carb when looking at it from the side (fuel petcock side) and one at the bottom, I know the one at the bottom is a drain but not sure which one of the two uppers is the air/fuel mixture screw.
Thanks!

The one to the left is mixture other one is idle. Does your have the auto choke on the carb? If it does it is way hard to get right especially if its cold outside or inside for that matter.

[cleanone]

I guess it does, there isn't a manual lever anywhere. I really like this little bike, my boy has a blast on it, I'd like to fix this if possible. It sounds like crap when it's WOT, the owner at Desert Toyz (where we bought the bike) says he can modify the clutch for more speed?, what would this do? any idea? How do i go about leaning the bike out a little to test, I don't want to burn anything up if running it too lean, how do I know how lean is o.k..? I've done this (pipe/filters/jets) half a dozen times and have never run into a problem like this.
Thanks for your help,

[Tyler107]

my buddy works at a kymco dealer ill have him get a screenname.

[bowtiedmax]

I would like to say that the Kymcos are very good machines. We have raced and put the 90 to the test over and again and the motors are just plain strong. We are still using the same frame from all last year and this year of the nationals and all the play / practice.
We used the same motor case,transmission and crank all last year and up to race 9 of this year. We only switched over to play with different performance stuff.
We were doing really good this year but Dad (me) got alittle to relaxed and let a couple of dummy errors hurt us at a couple of races. And then Jesse broke his arm on the 2nd lap of Saturdays race in steel city (still finished 2nd). Then he raced Sunday under alot of arm wrap and asprin for a 4th over all. So the 3 races that we didnt do to well were not the machines fault but good old human error.
There is so much peformance potentual for these at alot less cost than a trx90.
Thanks

[badvox]

Originally posted by bowtiedmax
[And then Jesse broke his arm on the 2nd lap of Saturdays race in steel city (still finished 2nd). Then he raced Sunday under alot of arm wrap and asprin for a 4th over all. So the 3 races that we didnt do to well were not the machines fault but good old human error.
There is so much peformance potentual for these at alot less cost than a trx90.
Thanks [/B]

Oh wow!! I am so sorry to hear about Jesse breaking his arm. I hope it all heals well. He is one heck of a little racer for sure.

Tell him that us So Cal folks hope he gets better soon!!

Mike

[bowtiedmax]

Hello Mike,

So what do you think of that ASSCO ?? I remember seeing a few of them at Glen Helen but none since there.


Paul

[bowtiedmax]

Opps!! I mean AASCO !!
I quess I had to many SS's and not enough AA's
Paul

[mecheech]

Originally posted by cleanone
We purchased a Mongoose 90 for my son last year, good bike, no major problems. I added an aftermarket pipe, and upped the main jet to a 108 then 110. Put some holes in the air box lid as wll. Alos, cut the light green wire on the CDI box to up the rev. limiter. the bike cuts out at wide open throttle, sputters and sounds like it is hitting the rev limiter or governor. Any help would be greatly appreciated.
Thanks, adrian


Does the 90 have the same limiter on the clutch as the 50?

After we changed that on our 50 there was no more sputtering or stalling at top end just kept pulling.

[cleanone]

Not sure, is this limiter an electrical or mechanical governor? Is it in the casing with the CVT? Thanks!

[mecheech]

It is a sleeve that the front clutch sits on. Stock it has a lip to keep the clutch from completely engaging. I think Badvox had called it "race boss face". It was only like $16 at my dealer and just needed an impact wrench to spin off the clutch nut.

Like I said before the mod the quad would spit and sputter WOT, now it just keeps trying to pull.

[cleanone]

I'll get ahold of the dealer and see if it's available thru him. Thanks!

[badvox]

Originally posted by mecheech
Does the 90 have the same limiter on the clutch as the 50?

After we changed that on our 50 there was no more sputtering or stalling at top end just kept pulling.

The 90 does NOT have the sleeve limiter like the 50 does.

[bowtiedmax]

There is still a factory rev limiter "in" the CDI box that you can not do nothing about. We are working on a couple of differant units trying to find one that will work. So if it sounds like its the igintion is cutting out, then it might be what it doing. I am not sure but I think its at about 7500-7800RPM. I chased this "breaking up problem" for most of this year untill Jesse wore a helmet cam at a race. Then about 3 weeks later when the DVD arrived and we was watching the race I was amased at how much he was on the limiter. When I commented to him about it, he told me thats what he kept talking about after each race. Well the helmet cam rental was moey well spent.
The 90's have a "shoulder" on the variater boss that limits the travel. You can tell if it is still there by pulling off the variator and the shaft that the inner half of the variator slides on should be the same size from end to end. If it has a shoulder at one end then just go to your Kymco dealer and by one without the shoulder. This will help out alot with acceleration and top speed.
Remember the rev limiter was talking about is differant then the green wire that gets cut.
Paul