I did a 1 mile away and back with gps and only got 66mph.Ive read numbers alot higher
on here.Ive got 15-40 gearing with 22in Razor 2.Hmf slip on.Jetting seems right no sputters.

Were those topend numbers just imagined in the 70s.Or should i be looking for a problem.

 

What altitude is Whitmorelk, Michigan, and how much do you weigh.

 

If he is running a mile than weight shouldnt have too much affect unless he is around 300. I am 220 lbs, hmf/ported intake/K&N in the box with lid on, and I got to 73 mph, and that was with 15/40, stock tires with 9 psi, and was not at the limiter yet (our field is small, have to shut down early)

How long did you sustain top speed? I have noticed if my gps is in my pocket and I only hit top speed briefly, it dosnt have time to catch up and then gives a lower reading.

 

A gps doesn't always give an accurate reading. Especially when climbing or descending hills they can get thrown off by as much as 25% faster or slower. The most accurate way to measure speed is to get a real speedometer. but that's just my suggestion of what the issue could be. 66 definitely sounds a little low for a ds

 

15/41 gearing, 22 inch bearclaws...highway for about a mile and at my rev limiter its 78.5-80mph on gps...the gps has been proven accurate many times ive got 5 psi in the rear tires...it seems my top speed numbers are always higher than others i dont no what to say about that but i no my speed is right.

 

Ok this happend a couple weeks ago, i was loosing top speed and thought it was just me geared to high with the 15/40 gearing and 22 inch bearclaws, it never felt like anything was wrong, no smoke from exhaust or crank case vent, and it pulled good. Well a couple rided after smoke starting pooring outta my crank case vent and my engine was making very bad noises. The next day i took her back to a local dealer..warenty was over and it turns out the top bring broke and a piece fell off wrecked the jug banged up the head prettty bad and my piston was junk...the dealer got me a deal with bombardier they paid 3/4 the final price on everything..they said my psi on the engine was like 70 at the time and said my top ring must of been gone for along time...it has never run better than now with my new piston and jug..my oil was always very black before but it never used any so i thought nothing was wrong..no smoke untill it finally just went that day and screwed over everything...now the oil is nice and clean and it stays that way....maybe you should do a compression check before something happens to you like it did to me. The only sign i got was my ds not pullin top speeds as easy as before otherwise it took off the same and everything. Bombardier thinks that it was a put together error, and it must have been.

 

We were at sea level.I weight 160 so i figured i was at top for a while.I was on a gravel road
so i probly lost a little there.
The cr 250 got high70s and the banshee got 71.

What should my compression be at?
Dunerider650 you trying to give me nightmares.[img]i/expressions/face-icon-small-smile.gif[/img]

 

i it 135 km/h that about 75 mp/H sound like im running in the pack

 

Using a 15/40 and 22" tires you should be around 85 mph with everything else stock.

 

haha...it was a nightmare for me just glad bombardier paid 3/4 the price even with the warrenty over...i think the normal compression on a stock piston ds650 should be around 165?