I have just bought a DS650 for myself and the DS90 two stroke for my 10 year old. He wants a little more power, but can't find any after market items like a pipe or air cleaner am I the only one with the DS90?

I took my DS650 to have it fixed because it sounsd like it is studdering when I open it up or clinbing up a hill even though it has the speed and power. The dealer said Im hitting the limiter. I have a hard time beliving that because I don,t give it evey thing it got and it seems to happen while Im working my way up to speeds in each gear or could it be he's right on. If am hitting the limiter that quickly what type or spec's should I be looking for in a aftemaket. Wanted to solve this issue before making any mods like jetting so they could not blame me for this problem. I live in L.A. If anyone knows a good service company that could fix or assess under the warrentee[img]i/expressions/face-icon-small-confused.gif[/img]

 

Well on the DS90, it is pretty new, but is manufactured by a taiwanese(sp?) company that makes a lot of the mini quads. I am not sure who it is though. I would think you could find parts that would fit, but might be actually for a different brand name, maybe someone else can help you out.

On the 650 questions, yes it does sound like you are hitting the limiter. I had the same problem with mine as soon as I really started riding it. There are several companies selling them and you could do a search and probably get more info than you want.

I have the ron wood cdi it has no limit and advances the timing a little. Works well. here is his site

Knutz also sells a cdi, it is team pami. I dont have a site for him, but here is his phone number 1-702-236-6852.

The above two have no limiter on them. Graydon makes one with a limit about 9300 rpm I think. I believe it is a little more expensive then the others. Alba also makes one, but I dont know anything about it.

Hope that helps. I would change the cdi out and I bet that solves your problem. I have missed shifts and stuff and never caused a problem with no limiter.

Bat

 

If you don't think your hitting the rev limiter, a simple check is the spark plug. You may, or it sounds like you may be running rich. If the plug is black then you will need to re-jet. If it stutters at mid throttle only and clears up at full then you can lean out your needle. If it stutters mid thu full, then you will need to change your main. Bottom end would be pilot jet.

The are some serious pro tuners on this forum, you might want to do a search on carb or tuning or jetting on this forum. The people here have covered alot of problems.

As fas as your DS90, I haven't got a clue. The parts for the DS650 just started to become available.

Good luck!

 

Make yourslef hit the rev limiter intentionally, like in 2nd gear on a straightaway, so you can hear and feel what happens. When you get high in the revs and reach 7700rpm, the spark will be intermitently cut off, and cause the motor to miss and not rev any higher. Do it several times so you are really sure what the rev limiter is, does, and feels like. Then you will be able to determine if the symptoms you have while trail riding really are the limiter, or a carb tuning issue. If your bike is stock, then jetting should be fine, unless the bike was used and somebody screwed with it.