Yea, that's quite a first post, but it is a very informative one. Good to know! I've always marked the tensioners with a piece of tape, but I never thought of checking it with a string. Now I have to do that everytime or I will wonder from now on if it's in line with the front.

 

I used to use the string technique, especially to square 4 speed trans/eng with open primary. Laser pointers got so cheap a few years back that I now use two of them. The 8' tubes wouldn't last very long in my shop either.

 

my dad taught me the string method yrs ago, and have used it on 4 wheelers several times over the yrs.. my dad being a semi mechanic and working for a family business they didn't have the money for a proper alignment machine.. he would align rear axles, frt ends, etc with a string and level..



my question on bikes is, how do you make sure the frt tire is perfectly straight ?

 

Why are light tubes used, do you know? It seems they would't last long as you said and that wouldn't be my choice of alignment either.

 

My guess is near-perfectly straight, and not too expensive.

 

I'd have to agree, straight and cheap. The lasers make the wheel alignment easy as well. I still prefer string or a flat piece of 1/2" tempered to align compensator and clutch basket.

 

I always used the drive belt. If the drive belt is tracking too close to the outer edge the wheel is slanted right, if it is too far to the inner edge it is slanted left, if it is in the center of the drive pulley you should be damn close to straight.

 

Been using this one for years. It's amazing how accurate it is. Many times I've had someone using a tension checking tool and I've said, "Wait, watch this". Tighten it up till you can get 45 degrees. 90 is too loose and 30 is too tight. After setting it, I had them check with their tool and viola, perfect every time.