Axle diameters

[kingoldrum]

Anyone happen to know the front and rear axle diameters, or have wheels off at present to quickly measure? I am trying to build a tire mount and balance set-up, and won't learn this for myself until I get the wheels off, which is too late (from a motorcycle down-time perspective). Thanks

 

[olsonm3915]

If you go to Yamaha's website and use the parts fiche application, you can look up the part numbers of the wheel bearings and Google those part numbers to determine what industry standard bearing numbers, and hence what their IDs are. Based on doing just that. and checking that a 2007 and 2005 use the same wheel bearings I will go out on a limb and say both front and rear axles are 20mm. If I'm wrong then sorry but it might be best to simply measure what you've got.

Or you could have gone to the '03-05 Bin 'O Facts and found out the same bearing information too.

Why do you need to know the axle diameters? I built a wheel balancer and later bought one, neither design depends on the axle being any particular diameter. One of them (the one I made) uses the bike's own axles to balance the wheel on two metal rails, and the other one I bought at Harbor Freight (and immediately bought a replacement shaft at McMaster-Carr since the HF shaft was so shitty) uses a precision shaft and two cones to center the wheel on its bearings, then the balancer shaft rests on some low friction bearings. Both designs work well although the homemade one is a little more fiddly since you have to carefully level the metal rails each time you set it up.

 

[kingoldrum]

If you go to Yamaha's website and use the parts fiche application, you can look up the part numbers of the wheel bearings and Google those part numbers to determine what industry standard bearing numbers, and hence what their IDs are. Based on doing just that. and checking that a 2007 and 2005 use the same wheel bearings I will go out on a limb and say both front and rear axles are 20mm. If I'm wrong then sorry but it might be best to simply measure what you've got.
Or you could have gone to the '03-05 Bin 'O Facts and found out the same bearing information too.

Why do you need to know the axle diameters? I built a wheel balancer and later bought one, neither design depends on the axle being any particular diameter. One of them (the one I made) uses the bike's own axles to balance the wheel on two metal rails, and the other one I bought at Harbor Freight (and immediately bought a replacement shaft at McMaster-Carr since the HF shaft was so shitty) uses a precision shaft and two cones to center the wheel on its bearings, then the balancer shaft rests on some low friction bearings. Both designs work well although the homemade one is a little more fiddly since you have to carefully level the metal rails each time you set it up.

 

[kingoldrum]

If you go to Yamaha's website and use the parts fiche application, you can look up the part numbers of the wheel bearings and Google those part numbers to determine what industry standard bearing numbers, and hence what their IDs are. Based on doing just that. and checking that a 2007 and 2005 use the same wheel bearings I will go out on a limb and say both front and rear axles are 20mm. If I'm wrong then sorry but it might be best to simply measure what you've got.
Or you could have gone to the '03-05 Bin 'O Facts and found out the same bearing information too.

Why do you need to know the axle diameters? I built a wheel balancer and later bought one, neither design depends on the axle being any particular diameter. One of them (the one I made) uses the bike's own axles to balance the wheel on two metal rails, and the other one I bought at Harbor Freight (and immediately bought a replacement shaft at McMaster-Carr since the HF shaft was so shitty) uses a precision shaft and two cones to center the wheel on its bearings, then the balancer shaft rests on some low friction bearings. Both designs work well although the homemade one is a little more fiddly since you have to carefully level the metal rails each time you set it up.

Thanks much for the reply. I looked in 06 Bin o facts, but could not find a mention...did not try the earlier. The bar stock I have available is .75", so was afraid it might be too big. I kind of slowly construct things, and did not want to pull out the axles till I had too.

 

[lnewlf]

Watched them balance wheels at Loudon, NH, in the pits. Those guys are fast and they use a shaft that is smaller than the axel. All the weight is exactly on the top of the shaft so diameter doesn't matter. I have several shafts and use the largest that will fit for strength.

 

[olsonm3915]

Watched them balance wheels at Loudon, NH, in the pits. Those guys are fast and they use a shaft that is smaller than the axel. All the weight is exactly on the top of the shaft so diameter doesn't matter. I have several shafts and use the largest that will fit for strength.

Could you expand a little on this method of balancing? It's not clear to me exactly how it works.

These are my balancers:

https://www.visi.com/~olsonm/med_homebrew_tire_balancer.jpg

https://www.harborfreight.com/cpi/ctaf/Disp...temnumber=98488

My homebrew one uses the wheel's own axle and relies upon the metal crossbars being level. Oftentimes a wheel will simply rotate on its own bearings while the axle remains stationary. If the bearings or seals have too much friction, the axle rolls along the rails. Either way a very good balance can be obtained quickly, but as I said before, it is critical that the crossbars are level otherwise the wheel rolls to one side or the other irrespective of its balance.

The Harbor Freight balancer is more straightforward, but as delivered did not work as well as my homemade balancer because the cheaply made shaft had too much runout. Each 0.001" of runout translated to about 1g of imbalance, and the shaft on my balancer was out as much as 0.010". I replaced it with a precision 1/2" x 14" Thomsom shaft (6061K431) purchased from McMaster-Carr.

 

[kingoldrum]

Watched them balance wheels at Loudon, NH, in the pits. Those guys are fast and they use a shaft that is smaller than the axel. All the weight is exactly on the top of the shaft so diameter doesn't matter. I have several shafts and use the largest that will fit for strength.

Makes great sense LoneWolf, and avoids my having to fashion "centering" cones.

 

[lnewlf]

Watched them balance wheels at Loudon, NH, in the pits. Those guys are fast and they use a shaft that is smaller than the axel. All the weight is exactly on the top of the shaft so diameter doesn't matter. I have several shafts and use the largest that will fit for strength.

Could you expand a little on this method of balancing? It's not clear to me exactly how it works.

These are my balancers:

https://www.visi.com/~olsonm/med_homebrew_tire_balancer.jpg

https://www.harborfreight.com/cpi/ctaf/Disp...temnumber=98488

My homebrew one uses the wheel's own axle and relies upon the metal crossbars being level. Oftentimes a wheel will simply rotate on its own bearings while the axle remains stationary. If the bearings or seals have too much friction, the axle rolls along the rails. Either way a very good balance can be obtained quickly, but as I said before, it is critical that the crossbars are level otherwise the wheel rolls to one side or the other irrespective of its balance.

The Harbor Freight balancer is more straightforward, but as delivered did not work as well as my homemade balancer because the cheaply made shaft had too much runout. Each 0.001" of runout translated to about 1g of imbalance, and the shaft on my balancer was out as much as 0.010". I replaced it with a precision 1/2" x 14" Thomsom shaft (6061K431) purchased from McMaster-Carr.

My homebrew balancer looks almost identical to the HF unit-but by the time I bought wheels ,bearings, stock and paint and welded it all up I probably had close to $60 int it. The shaft will rotate regardless of it's diameter. I don't like the cones because if they are not exactly positioned they might cock the wheel and throw off the balance. You are correct that any runnout or flex in the shaft will create an imbalance. I am a lot less anal about getting it perfect-we not talking turbine fan but rather approx 800 rpm at 60 mph. Even the small amount of bead lubricant running around inside the tire can screw up the balance process. Like hand grenades-close is good.

 

[olsonm3915]

You are correct that any runnout or flex in the shaft will create an imbalance. I am a lot less anal about getting it perfect-we not talking turbine fan but rather approx 800 rpm at 60 mph. Even the small amount of bead lubricant running around inside the tire can screw up the balance process. Like hand grenades-close is good.

My thinking is, if you're going to the trouble of balancing a wheel at all, why not get it as close as you can? If 10g of imbalance is acceptable, then just buy the HF balancer for $60 rather than making your own with $60 worth of parts. I can feel 10g worth of imbalance at the sorts of speeds I sometimes hit cruising out west. To me, spending the additional $7.50 + $4 shipping on the Thomson precision ground shaft for the HF balancer was well worth it. I did check the runout on the centering cones of the HF balancer and they were plenty good. I agree if they have runout it will negatively affect the balance in the same way shaft runout will. To be honest I stop adding and subtracting weights when I get down to +/- 1/2 of one of the 7g stick on weights. So, yeah, I am picky.

 

[lnewlf]

You are correct that any runnout or flex in the shaft will create an imbalance. I am a lot less anal about getting it perfect-we not talking turbine fan but rather approx 800 rpm at 60 mph. Even the small amount of bead lubricant running around inside the tire can screw up the balance process. Like hand grenades-close is good.

My thinking is, if you're going to the trouble of balancing a wheel at all, why not get it as close as you can? If 10g of imbalance is acceptable, then just buy the HF balancer for $60 rather than making your own with $60 worth of parts. I can feel 10g worth of imbalance at the sorts of speeds I sometimes hit cruising out west. To me, spending the additional $7.50 + $4 shipping on the Thomson precision ground shaft for the HF balancer was well worth it. I did check the runout on the centering cones of the HF balancer and they were plenty good. I agree if they have runout it will negatively affect the balance in the same way shaft runout will. To be honest I stop adding and subtracting weights when I get down to +/- 1/2 of one of the 7g stick on weights. So, yeah, I am picky.

Agreed! Wasted my time building my own except that at the time the HF unit was not available and I was looking at almost $200 clams for the others. I think I will check out the Thompson shaft as it is probably better than mine. I usually stop futzing around when I get within 7 gm. I have had riding buds who were concerned about the weight of the masking tape that I used to hold on the weights.

 

[MT home]

I use the closest size of drill rod that fits. Nominal sized metric drill rod may not fit, if the axle is slightly undersized, as is the case with my Airhead BMW. I get drill rod through MSC, an industrial supplier. (Free 4,000 page catalog - anybody who offers 135+ pages of drill bits can't be too shabby.) I cut down a 3' length to get to a more manageble size. The "closest size" rod system matches up to what I've seen the tire techs doing in AMA Superbike road race pits.

My "home made" wheel balancer uses ABEC grade 5 bearings (out of replacement wheels from a kid's Razor skooter) mounted on a VAR bicycle wheel truing stand I own from my days working in the bicycle business.