it has full white bros exhaust system, uni air filter, stage 1 cam, 160-165 dyno jets, 22" rear tires, 13 tooth front sprocket and stock sprocket on the rear. almost bald tires. i tested it yesterday with my gps on some semi loose gravel/dirt road with 0wind. its heavy because of all the things it has but i thought i would be hitting around 75-80mph. is my bike OK? or should it go faster?

 

it will reach the speed you desire with a 14 tooth front.

 

i know that

 

If you know that, then why are you asking the question in the first place? Top speed is a function of RPM and gear ratio. Assuming that you aren't power limited, because of your mods, then one must assume you're hitting the RPM limiter. The only way to increase speed then, is to increase the RPM limit or increase the gear ratio (front sprocket)or tires that have more tread and are therefore larger diameter.

 

i dont want to argue, i just assumed my bike would be hitting 75-80 with the set up i have now. i dont want to go that fast i just thought i was reaching that speed with my set up. and i was asking if my speed was correct for the set up i have.

 

Okay, me neither...

Assuming that your real tire diameter (twice the distance from the flat patch on the ground to the axle) is really more like 19" (would be about 20 with new tread), and assuming that due to load and wind resistance in 5th gear that you top out around 7500 RPM, you should expect to see around 73MPH. Depends on how well you 'tuck' in to optimize air flow.

Rule of thumb is somewhere between 7500 and 8000 RPM at top end due to air resistance, primarily. Drag goes up as the square of velocity, so it doesn't take too much more speed to greatly increase drag and offset engine improvements.

A good treatise on this subject that contains a link to a simple speed calculator:

<a target=_blank class=ftalternatingbarlinklarge href="http://www.raptorforum.com/index.php?topic=6705.msg64129#msg64129
">http://www.raptorforum.com/ind...g64129#msg64129
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Good Luck!

 

Thats only 30 MPH faster than my stock 350 2x4 Big Bear.. lolol...

 

I had my 400 AC 4x4 auto up to 75 mph - so what if it was in the back of my pickup..

 

I think your bike should be a lot faster then 71.8.. I have the 02 660 and have reached 92mph. Trust me, all the tickets I had to pay dont lie. You seem to have a good set up. I have a stage 1 hot cam, 11:1 wiesco piston, stage 1 dyno jet kit. Not sure of the jet size.... Cfm custom air box (no lid), uni filter, full big gun evo exhaust, 20x11x9 holeshots on the rear. I have seen bone stock raptor's at a drag strip hit between 80-86 mph. You have a problem somewhere. How much do you weigh????????

 

180lbs