I have a 1998 Suzuki DR 650 with 12,000 miles on it and have thrashed it consistently since buying it. Bridgestone trail wings are great on the street, footpeg scraping good. Okay on fireroads, not good in sand. New chain and sprockets at 12k, syntec 5/50 every 3k miles.
No problems at all, lots of grins, and sad sport bike riders on tight twisties. At the dragon (129) it will beat my own ZX9, not by much but it will do it.
Dynojet, jet kit, gutted airbox, took spark arrestor bolts out of pipe for breathing. BIG improvement over stock.
15 tooth front sprocket, 44 back with 520 chain 8,000lb GSXR chain is what it needs.
With jet kit it does great with this gearing.
Best value for money and fun I have ever had on a motorcycle, and I have owned a bunch of them.

i have a 96 dr 650se with 17000 miles on it and yes it,s superb .i've just read your writeup, where are these spark arrester bolts?ihave a uk model bike and any improvement would be nice ,especially for free.i dropped the front sprocket to 14 teeth which is just about spot on although i also have a 43 tooth rear which i shall fit in the summer banzai baby

Can someone explain to me what effect changing the front and rear sprocket sizes has on the bike. I have been told a couple of times but I can never remember which way it works.

smaller front sprocket = more rpm
bigger rear sprocket = more rpm

bigger front = less rpm
smaller rear = less rpm

all at any given road speed.

think of it this way:

If you had say 10 teeth on the front and a rear sprocket the size of the rear wheel with say 500 teeth, that little front sprocket would have to turn 50 times for that rear to turn once. That's very high revolutions for one turn of the rear wheel! (should be good for about 20mph tops)

OR if you had 50 teeth on the front and 50 on the rear, it would be only one turn of the front to get one turn on the rear - very low - 1 - revs to turn the rear once. (500mph coming up...)

Clear?

------------------
Grant Johnson

Share the Dream!
at: www.HorizonsUnlimited.com

The arrester plugs are in the end of the muffler underneath. One right at the end and the other at the front end where the pipe and muffler join. These let it breathe much better without a big increase in noise. Rejetting would be necessary if you do this with stock jetting
nzzx9

more teeth front sprocket higher gearing, more teeth rear sprocket lower gearing. The front ideally should have a 15 on it for chain life. But a 14 with the stock rear works great on these bikes. If you jet it then it will pull higher gearing easier. 15/44 has worked well for me with the extra power.