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The_AirHawk 10-12-2009 09:50 PM


Originally Posted by dburton07 (Post 225900)
I looked on ebay and all they have is the FMF pipe. And yes it is an 88. Making an adapter for a newer one is not a problem as I am a machinist. Should I be all set with a silencer that is made for a 200 but not my year?

Gearing question too. I dont really know what changing the tooth numbers do? Im pretty sure it has 14 in the front and 49 in the back, and while looking up new sprockets because i need them, what would it do if I went up or down in teeth? Never really knew what it did.

Well, being a machinist - you should be able to figure it out easily.

What happens to your surface speed when you go up or down a couple of gear-teeth on your lathe? (or move the drive belts from sheave to sheave, if it's not gear-driven)

Please don't tell me you've never worked with equipment old-enough to have either of those........

dburton07 10-12-2009 10:00 PM

Never even though of it that way..... Maybe I should go to bed now....

The_AirHawk 10-12-2009 10:10 PM


Originally Posted by dburton07 (Post 225902)
Never even though of it that way..... Maybe I should go to bed now....

No problem. It's one of those things that you "knew" the answer to already - just took a bit of a jar to realize it.

As to the amount and direction of change; well, what do you want to DO?

Changing the front sprocket generally has a bigger effect on the bike than the rear - BUT: often you're limited in the clearance around the sprocket as to how much larger you can go. Also, there are some bikes that, obtaining the STOCK sprockets is hard-enough - larger front/smaller rear is all but impossible for these. I don't believe the KDX falls in that category, though.

dburton07 10-13-2009 07:03 AM

I was just curious if it would give it more low end grunt, say for instance going from 14 teeth to 15 in the front and 49 to 48 in the rear, would it make that much of a difference? And wouldnt that affect top speed as well? Not like that really matters but just wondering, maybe I'll go check out all the motors and gears I have for my Xmod, that should give me a better idea.

And thanks again guys (gals too if any) for all the help and info.

pplassm 10-13-2009 07:39 PM

If you do that, it will make your bike sluggish. Stay with stock gearing.

dburton07 10-13-2009 08:25 PM

I planned on it, was just curious.

pplassm 10-14-2009 06:21 AM

Neat job you've got there:

Central Maine Pyrotechnics

dburton07 10-14-2009 06:32 AM

yeah its a part time thing, but it is a blast. I consider it my hobby since I don't really have one, but now that I have the kdx, it'll give me something to do this winter.

dburton07 10-14-2009 09:15 PM

So i was cruising around dennis kirk and typed in 89 kdx 200 and 4 silencers came up. But 88 there is nothing. What is major differences between the years that would not allow 89 silencers to work on 88? If it is something dumb like tubing size is different or bracket location changed slightly, I can correct those no problem.

pplassm 10-15-2009 03:27 AM

89 was a complete redesign. Water cooled engine, 2 disc brakes.

You may be able to adapt it. Get a cheap used one off Ebay.

Ask this guy:

Fredette Racing Products Beecher, IL (708) 946-0999

Jeff Fredette has won medals in 20 ISDT/ISDE's. Mostly on KDX's.

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