660 Top speed what am I missing?

Top speed on my 2007 600 rhino only 268miles is 47 down hill looking to hit 50-60+ I spent some money hoping for the speed. Let me know what I can do or your mods you have and your top speed.
Jbs sheave
Orange spring
Plastic spacers
siphon break
stock exhaust with tip with baffle removed
tri-fire cdi box
stock jets, running 91% fuel, stock plug,
27" tires
2" lift
rear cage with seat

Let me know what I can do or your mods you have and your top speed.

What weights did You put in your sheave ?

I think 16g the number is 3015-16g

That may be part of Your issue. I think You would do better with 14's, especially with the 27in tires. My Rhino is an 07 660 MSD charge, JBS sheave,16gr weights,anti friction washers,26in tires, exhaust tip, K&N filter. I hit 54 when the rev limiter kicks in. The big difference in mine and Yours would be tires and extra cage with seat. The only thing else different is I have rejetted mine to a 45/155 setup with 04 style intake

Firefighter whats your elevation?

you need my air fuel gauge...

i say your lean..

lean or rich. what's your jetting? also I would use a GPS or smartphone with a speedo ap, don't just rely on the cluster, they are off more than not.

What's happening is you have a JBS sheave and a HW CDI. You get the two of them together and they start fighting at WOT.

wisertooshort wrote:

Firefighter whats your elevation?

sea level

i can get about 48-49 hoping the sheeve will give me a few more ,but bigger tires really nock you down

Pokahpolice wrote:

What's happening is you have a JBS sheave and a HW CDI. You get the two of them together and they start fighting at WOT.

lol...thats funny ..i dont care who you are..maybe todd lied to him about what it does...lmao

Pokahpolice wrote:

What's happening is you have a JBS sheave and a HW CDI. You get the two of them together and they start fighting at WOT.

lol

HAHAHAHA!! GOOD ONE!!

Thanks for all the help . I bought a new spark plug the ngk 2202 I am at 3000' elevation. I think i'm lean running the stock main jet. But time will tell. But still don't see how that alone will decrease my top speed by 10 mph or more. should I be running 14g weights? And i got a speed app for the phone I will use.

lean will kock off 20-30 mph if its lean enough....that exhaust is modified so thats prolly what it is...lean

i dont have a sheave yet but when i first got my 04 660 i could do 38 with stock tires hitting the limiter. put the msd charge on and wow i hit 49, i put my 27" itp xtr's on and bam back down to 39 the tires way alot more than stock tires if i get to 50 after my sheave and weights i will be extremly pleased with not having any more engine mods

to lean not good, and more wt. and bigger tires eat horsepower, just my thoughts

I was a little mis leading on the weights. What I should have said was with the taller tires and added weight of cage and back seat, the 14gr weights will get You to that top speed quicker. Not necessarily more top speed ! Dunerdan, if I remember correctly, had a 4 seater and ran 14gr with great success.

Firefighter wrote:

I was a little mis leading on the weights. What I should have said was with the taller tires and added weight of cage and back seat, the 14gr weights will get You to that top speed quicker. Not necessarily more top speed ! Dunerdan, if I remember correctly, had a 4 seater and ran 14gr with great success.

yup I have 26's 4 seater, intake, exhaust and JBS sheave 14g weights.

I hit 55 on flat road 57 if I revved it way out, 45 in the sand wash (biggest improvement on 14's) and I could hit 61 on downhill

the 14's will help with 0-40 the most and 50-57ish also. I could hit 60 with 2 seater and 25's with 16's.

TUNING and a good OPEN filter intake (unless you ride water) are a huge improvement also.

I had 45pilot 1.5 turns
fat washer under needle
and 157.5 main. Dan 13.7 and sea level and never popped or ran rough up to 8k feet

took me 2-3 hours of tuning over time lol

I am not an Engineer, but when I put taller tires on my truck, my speedometer was off by 5 mph, I would think the same goes for a Rhino. So for those that have taller tires may want to check a GPS speed against the speedo...Just my opinion.

Ok with all the new carb work, filter,plug using a gps for speed I got it up to 49mph. So what should I try next?

i had one yesterday that was 10 mph short and the throttle cable had stretched..it was only opening to 3/4 throttle....if every 660 on here and 700 checked theirs they will find it prolly needs adjusted...hot rod style is you have to get it all..lol

i bet everybody is checking there throtle cable adjustment now! thanks james

Thanks for the tip james