MHR vario on a street setup

[quicksand]

This is the following setup:

s6 sport cyl.
yasuni city 16
stage six 21 mm
hebo crank
mhr reedcage without venturi
malossi yellow spring
stage six clutch


my questions are that is this variator not suitable for the setup? would it run better with a stock one? because it is weird we tried 3.8 rollers on it and it was extremely light, then tried 4.5 rollers it went good at the beggining but still way too light, so i ordered 5g 5.5, 6, and 7 gram rollers to test, do yu think that this has something to do with the variator?

and would it run better with a stock reedcage and polini reeds or with the mhr one?



thanks, amir

 

[adas]

Aloha, Variator and reed cage are ok. You just need to know how to tune your rollers. Do you have a Tach on your bike, if so then find your power curve.

Several easy and general ways to do this.
1: slowly accelerate and find at what rpm your power comes on and/or go full rpm with light weights and see at what rpm your power stops (do not count overrevving). If for example your power stops at 11,000 rpm then the very rough rule is that the power curve is about 25% to 30% of your rpm range. 11,000/25% is 2750. Subtract that from 11,000 and you get a power range of 8250 to 11,000 rpm. With the middle of 9625 rpm. This is the engine speed of 9625rpm that you will want to tune your roller weights to. This again is a VERY ROUGH estimate (max power mostly is not in the middle) and according to how well your cylinder is matched to the pipe, how wide range rpm is your pipe, 25% to maybe 33% of your total rpm range is about average for a street pipe. Then right away you need to tune your carb to be sure you are not running rich or lean.

frank

 

[tiba_karotsu]

quicksand,

dude you just gotta learn how to tune your vario but in order for you to tune it to it's fullest you gotta have lots of rollers with different weights, start light on the weights and go heavier when the engine can take it, this is how i tune the vario & you'll be surprised at how much weight i add everytime i go for a testrun for race engines but for your setup try adding +1g to your total roller weight everytime you do a testrun (28g, 29g, 30g etc etc)

 

[quicksand]

hi, thanks for the replies, today we have played with the rollers and found a good weight 37.5 g and the bike goes perfect lifts up nicely and now all is left is jetting. the bike revs nicely at high rpm but at low it sounds abit 4 stroke this is due to a too big jet right?




thanks for replies, Amir.

 

[tiba_karotsu]

hi, thanks for the replies, today we have played with the rollers and found a good weight 37.5 g and the bike goes perfect lifts up nicely and now all is left is jetting. the bike revs nicely at high rpm but at low it sounds abit 4 stroke this is due to a too big jet right?




thanks for replies, Amir.

it could be a big pilot jet or too high needle clip adjustment, the main jet has nothing to do with your engine "4stroking" at low throttle openings your pilot jet & needle thickness/taper takes care of that.