HELP WANTED ! 12 hd beltdrive single

[big jesus 151]

Hello fellow enthusiasts, I am putting the finishing touches on my 12 hd & was needing some info.Anyone have the mathmatical equasion for figuring belt length. Any tips from the wise on this subject would be greatly appreciated. Thank You Carl / Pusherman Racing

[23JDCA 808]

http://www.durabelt.com/beltlengthcalculator.php
A leather belt on flat pulleys should be one of the easier examples to figure out. I found this by googling belt diameter calculate. (I don't use a belt ...preferring suspenders.) ...bill in oregon

[big jesus 151]

1912 hd suspender drive !!

Well you were correct, I went to my grandfathers war chest & got one of his suspenders & put it in on my bike. It goes 50 MPH now, I calculated this with my Timex. Best of all, I took the stretch out of it, by adjusting the clasp !!!This is the Hot set up boys! See you on the track!
All joking aside,thank you for the reply & info !!! Carl

[c.o.]

and here I've been using panty hose.............no wonder I always come in last place!!

[aka HAWG]

carl

this idea may help - I took some strips if thinner cardboard cut it to strips and stapled together lengthwise till I got the correct length. then took it to the leather shop for cutting of the leather

it seemed to work on my excelsior

aka HAWG

1914 excelsior
1940 indian military chief
1965 xlch sportster
1971 bsa chopper

[Paps]

I use a tailors tape to do the inside measurements. You mark the old belt at one point. This is where you sart the tape. Walk the tape, using to hands and fingers all along the diameter, keeping the tape flush to the inside of the belt as you go. Once you reach the mark again. you have your indise measurement. Buy a good tape though. A cheap Asian tape is off a mile. I checked my tape against a 24" machinist scale. Take the tape with you to your belt suppliers. Measure theirs to match. This type of measuring works on all types of belts, as long as you know to get the correct pitch for v belts, or correct teeth for cogged belts. Flat belts are easiest to measure this way. Paps

[Rod K]

Leather belt

Interesting information in the above posts. Does anyone sell the finished belts?
The only place I've seen them is Comp. Dist. Catalog. He shows them for 1910 to 11 and
1912 to 14.Has anyone ever used these, do they fit ok??? Thanks Rod

[big jesus 151]

Help Wanted

Hello Gents,I was kind of thinking along the lines of : Let's pull the rear wheel forward to 0, pull back your belt tensioner lever to the last notch, then measure your belt with a flexible tape ( tailor / vinyl contractor ) along all of your pulleys. Then you should subtract : ( stretch factor) keeping in mind how much give you should alow for engine idle while belt is disengaged,etc.
I have heard of belt stretch problems from other members.I was hoping to find the formula to build a belt or order one without doing it twice.Anyone with tesimony on Lonniepop belts ?? Thank You All..Carl-513 407 2575

[Robert Luland]

Half of the diameter of both pulleys + shaft center to center times two = belt length. Would I lie to you. As the freandly A/C man thats how we do it in the field. This is a good item to keep around.