Belt length and tension?

noobe q havent found a direct answer about this topic yet. i figured id ask since some of you probably use the same, what length belt would you use for say diyes v4 mount and pulley kit on caliber trucks w 6374 motor? i know it can depend on # of teeth, lets say diy standard kit w 16t and 36t?

Have you searched? I found it in like, 5 min, but here it is.

Also for any other quick questions just post in noob questions topic

wow i feel dumb .== thank you!

ohh ok cool thanks

Iv’e been using 265mm with Diy’s V4 mount. 16/36 and 15/36 gears. The V4 mounts have a wide adjustment range and I think the longer belts are better because you will have less angle comping off the pulleys so more tooth contact. For tension, I recommend running your belts as loose as you can without slippage. Running them too tight can put extra stress on the motor bearings and increase drag. I think it also helps to smooth acceleration and braking slightly as the belt gradually tightens during transitions.


I thought the same thing. It seems you would get a better mesh. The mechanical engineers I work with say that the shorter the belt the better. You want the largest amount of the belt in contact as you can get.

At least that’s what they tell me…

1 Like

I’ll bet there thinking is that less belt means less stretch. But in our application, I feel that more stretch is a good thing. Also, some have complained of belts breaking but I have never had a belt break running them long and loose. The only down side to this that I have found is If I need to brake hard and sudden, my belts will jump teeth. So for those who ride in heavy traffic, loose belts are probably not the safest option.

1 Like

I agree. I tend to run as short as I comfortably can on large pulled and a little long on small pulleys. On 15/40 I use 265mm belts, on 15/32 I use the same but move the motor out more to increase mesh. I usually leave my belts loose enough to push down 1/2 an inch on dual motor builds, single a little tighter.

That’s about how tight I run mine.

1 Like

There’s an ideal tension that belts should be run at and tools to measure said tension. The ideal tension is based on manufacturers specifications and also the application and transmission power required.

I usually tighten the belts enough to push them a little bit and get no drag at all, nevertheless I get belt slippage on nearly dead stops, which I really hate, this happens on both of my builds, currently runing 15/36T on 1st build and 16/40T on 2nd build.

I’m going to try to adjust the belts more even though I’m going to get some drag, I’ll tight them until there is almost no flexion of the belt, hope it’s not too tight, I’ll report back afterwards.

1 Like