Center to Center

STS · Jan 25, 2006

I was wondering if anyone out there has checked the center to center on their Apex or Attak?? Mine is out, but I believe it is within spec from Yamaha.

And I am curious if there is any way to remedy this, I spoke to my dealer and he says that there is no way of adjusting this, does anyone know if his answer is correct??

He also told me " If the center to center is out, depending on which way you may be able to fix this with a different belt, either longer or shorter, which ever the case may be".

Does that sound like it would work?? Sorry if I sound like I don't know anything at all, but I am very new to this and to be quite honest, I am trying to learn as much as I can about this. :rocks:

BADSLED · Jan 25, 2006

267-268.5 mm

Sno Cat · Jan 25, 2006

Better than buying a different belt is to adjust the height the belt sits in the secondary. This can be done by adding or subtracting washers behind the 3 bolts on the backside of the secondary. I set mine so the belt is just above flush w/the outside diameter of the secondary sheaves. The washers are available from a dealer or a variety of web-based Yammie suppliers. I don't recommend belts from other manufacturers, they don't last as long & they don't grip as good. You'll be forever trying to tune your clutches w/a non-OEM belt.

snowbeast · Jan 25, 2006

STS said:
I was wondering if anyone out there has checked the center to center on their Apex or Attak?? Mine is out, but I believe it is within spec from Yamaha.

And I am curious if there is any way to remedy this, I spoke to my dealer and he says that there is no way of adjusting this, does anyone know if his answer is correct??

He also told me " If the center to center is out, depending on which way you may be able to fix this with a different belt, either longer or shorter, which ever the case may be".

Does that sound like it would work?? Sorry if I sound like I don't know anything at all, but I am very new to this and to be quite honest, I am trying to learn as much as I can about this.

Yes so far all the short tracks i have checked were out by .030 with my center tool,and for the record they or the clutches were to close togeather,meaning your belt is to long,and acts like you are starting off in 3rd gear,yes add shims will tighten up belt or look for a shorter belt.

welterracer · Jan 25, 2006

Mine was off too.. had to add washers..

MyOutdoors · Jan 25, 2006

Will we gain or lose top end by adding enough washer to get the belt to ride a 1/16th above the secondary?

grader · Jan 25, 2006

you should not be compensating with shorter belts because the center to center is out, fix it. the rx1s were said to be solidly mounted and not adjustable but it is. the motor can be moved to set the c to c perfectly. this is critical if you want max hp to the track.

black john · Jan 25, 2006

c to c

this is very important c to c must be corret. and they are the same as an rx 1 which is ajustable. infact they are so ajustable that most guys had to build torq straps just to keep them right. if you c to c is out there total loss of performace no top end poor exeration and posably bad gas milage. theres only three bolts holding the moters in the rx 1 i would think that these newer sleds would be the same.

STS · Jan 26, 2006

Thanks guys, now I have some sort of direction on geting this problem solved :rocks:

Reaper · Jan 26, 2006

Mine was real shy, like 3mm short ! No idea how you can adjust C-C on the Apex ?

welterracer · Jan 26, 2006

What is in in INCHES??? i dont have anything that measures in MMs

Reaper · Jan 26, 2006

.12 inch or 120 thou.

25mm = 1 inch

No way to adjust C-C on Rx or Apex according to Yamaha.

grader · Jan 27, 2006

you can adjust c to c on both the same way.two bolts at front of motor and one long one through rear . loosen bolts, set to spec, tighten bolts and your done. on the rx1 there is a thick tab/flange that you can bolt a turnbuckle to. the other end can be bolted on at the front of the sled, i bought one with a hook on one end and hooked it over the frame. once c to c is set, tighten lock nuts on turnbuckle and your done. over 11000 miles so far and the motor does not move. the apex might be slightly different, eg. flange, but the motor can be moved for adjustments and should be locked once set.

snowbeast · Jan 27, 2006

welterracer said:
What is in in INCHES??? i dont have anything that measures in MMs

One mm is .0396 thousands or .040 3mm is .120 thou or almost .125 or 1/8 inch so if your c to c distance was 3mm that is alot almost 1/8 inch,you may want to move engine mounts if its that far off,the average i have found was like .030 thou not even i mm.

KnappAttack · Jan 27, 2006

Don't worry about center to center. It will ONLY affect shift ratio from low to high. You can compensate with shiming the belt deflection. With less ctr. to ctr. it will act geared down. Longer ctrs will act geared up. You are only talking 1-2% range. The ctrs can not be changed on the Yamahas. Only by what is avaliable in the slop in the motor mounts. Its not worth wasting your time guys. Mike Knapp#17

Center to Center

STS

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BADSLED

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Sno Cat

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snowbeast

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welterracer

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MyOutdoors

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grader

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black john

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STS

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Reaper

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welterracer

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