Overange setup, HELP!!

[gdr8]

I just started using a new Mollasi Overange pulley and variator this last weekend and I had a few questions.
I have this on a Mollasi big bore motor that has the 45 crank, with 160psi comp, PVL, 30mm carb with 48 pilot & 145 main and a 1/2" spacer, Gen III pipe, Koso adjustable clutch set to engage at 6200 rpm, Dave carters slipper clutch, gearing is 20t front and 29t rear with 28/11 trans gears. and I am running the 18x8x8 ITP's.
I started with 3.8 rollers and a 1250 maximm rear spring, and the overange belt, the bike sounded good and seemed to pull well but didn't seem to go real fast. I then went to 4.25 weights and a 1000 spring and it got better.
What is everyone else using for roller weight and rear spring on your quads? What should I do next? We run MX out here on the west coast.
Also I seemed to get flat spots on the rollers with only a race or two on them. I am using the Stage 6 rollers.
Any help would be greatly appriciated.

[dewutfan]

we are running almost the same set up but i am running 5 gram weights and 1500 torgue spring.. but you need to call Gary Fallon at G force powersports he is the master of this set up ... he will walk you tho every step and get your bike running smooth ... just my 2 cents worth .....

[nastynotchback1]

We are runnin the 1000 Max Rpm purple spring and i had to go up to 5.25 rollers to get it to have top end.Stall is set at about 6900 and it rockets out the gate with wheels up and runs like a raped ape on the top side.Belt runs up to 1/8th from the top.

my gearing is 19/35 with 70cc gears.

[gdr8]

Originally posted by nastynotchback1
We are runnin the 1000 Max Rpm purple spring and i had to go up to 5.25 rollers to get it to have top end.Stall is set at about 6900 and it rockets out the gate with wheels up and runs like a raped ape on the top side.Belt runs up to 1/8th from the top.

my gearing is 19/35 with 70cc gears.

I was running the high gears in hopes to help my top end, maybe I'm to high geared and to light of rollers. If I go with heavier weights and lower gears will that still give me the top end speed?
We run some bigger MX tracks that have some pretty long runs and we need the top end speed.

[nastynotchback1]

Originally posted by gdr8
I was running the high gears in hopes to help my top end, maybe I'm to high geared and to light of rollers. If I go with heavier weights and lower gears will that still give me the top end speed?
We run some bigger MX tracks that have some pretty long runs and we need the top end speed.

I had a set of 90 gears that went out and i changed to the gears we are running now and i had to go from 3.75 rollers to the 5.25 rollers to get it to run as good as it did before.i have never checked our top speed but it runs with some fast national level 70cc's on the top end.

[gdr8]

What gears are you running on the output shaft and on the axle?
You say "70" gears for the tranny, is that the 35/13's or something like that?

[gdr8]

Sorry about the first question, I forgot you had already told me you were running the 19/35 combo.

[nastynotchback1]

Originally posted by gdr8
Sorry about the first question, I forgot you had already told me you were running the 19/35 combo.

im not sure what the 70cc ratio is for the tranny gears

[jerkyboy]

50/70 gears are 31/13. My opinion is you need to change you sprokets, with the high speed 90 gears you need to be around
19/35. With the heavy rollers and that gear your keeping it out of its power band.

[glntamu90]

The Maximum RPM rollers are the best. Can't seem to make them flat spot at all. The Stage 6 rollers will flatten in 4 laps.

[wrhracing]

Are you using a 45mm stock style crank with a Honda/Yamaha piston modded to work or do you have the real Malossi crank and Malossi piston?
You might also use a "TINY TACH" to figure out the RPM the engine pulls.
The Pipe will also be a huge factor in MPH since it will contribute the upper RPM the engine will pull.
I would really use a stiffer spring then the Purple 1000 , it is a good spring but after a couple of hot rod laps it may not be strong enough to facilatate a strong takeoff.
Roller weight requirement really changes if you change the rear spring strength. A stronger spring will make the same weights act as if they are lighter. A softer spring will make them appear heavier.
Of all the belts available from Mallossi which one are you using? This too changes the way the engine is able to perform and can limit topend speed.

[gdr8]

Originally posted by wrhracing
I have a mallosi piston with a 12mm pin, stock type 45mm crank. The current pipe is the Hetrick Gen 3, I am using the standard overange belt that the kit comes with. I have the clutch set to engage at around 7k. Getting beat all the time on the holeshot. Tried a geen hulk spring with about 5 gram rollers, tried a red hebo and got better but still getting beat on holeshots. They are just pulling away.

Are you using a 45mm stock style crank with a Honda/Yamaha piston modded to work or do you have the real Malossi crank and Malossi piston?
You might also use a "TINY TACH" to figure out the RPM the engine pulls.
The Pipe will also be a huge factor in MPH since it will contribute the upper RPM the engine will pull.
I would really use a stiffer spring then the Purple 1000 , it is a good spring but after a couple of hot rod laps it may not be strong enough to facilatate a strong takeoff.
Roller weight requirement really changes if you change the rear spring strength. A stronger spring will make the same weights act as if they are lighter. A softer spring will make them appear heavier.
Of all the belts available from Mallossi which one are you using? This too changes the way the engine is able to perform and can limit topend speed.

[neveready]

The whole problem is the gearing guys...... high speed tranny gears with 20/29 and big tires!!! It'll never shift!!

Thats why the rollers are flat spotted, it cant overcome the gearing. Yet it needs a light roller to take off.

With those gears you'll need about a 17/38 with those tires and overrange, run a 5.5 roller and a 2000 spring with the 8779 belt.

With standard tranny gears you would want about 19/32 to 34 gearing.

my.02 get rid of those gears, it WILL affect the clutching!!

We ran them for the past 2 years!

[gdr8]

So I did just that, i got rid of the "high speed" gears and went to the stock 31/11 gears. I am using 19/32 sprockets. It runs way better!!
I am currently using 4.25 rollers with a 1500 maximum purple spring with a 611152 belt. I am considering trying a 1250 spring.
What do you think?

[Logan #34's Dad]

It's my opinion that the 152 belt is too skinny. We all try to get full belt pull on our front variator, If your variator cannot physically squeeze the skinny belt to the top then it is never going to get full pull. Plus if the belt is too long and the front variator does pull the belt to the top then the long belt will not go down in the rear pulley far enough to get maximum speed of the rear pulley. Ideally, you want the belt to come out of the top of the variator and as far down in the rear pulley as physically possible for maximum top speed. Think of a 10 speed bike.
The 8779 belt is the best available belt out there imo.