Author Topic: Gearing (Read 3681 times)

bcm · « **on:** July 03, 2016, 12:04:19 PM »

I just got back from sand mountain Nevada and was racing on drag hill, I got a 1988 trx250r with a ser 330 cylinder and a 4mil stroker. I was having a hard time trying to take off in 2nd gear and having to use 1st and noticed 4th would be still pulling by the top but seamed like it could be pulling better. I'm running a 13 38 and was woundering what would be better for dragging up steep dunes? Thanks for any help.

bcm · « **Reply #1 on:** July 03, 2016, 12:29:30 PM »

I also have a extra 36 sprocket in the garage but I'm thinking going up to a 39 or 40 rear would work?

Piediddy · « **Reply #2 on:** July 03, 2016, 11:42:51 PM »

Gearing is kinda trial n error, there's a lot to factor in, weight, paddles, length of swingarm etc. I like to set my bikes up to take off in 1st and get the bike out the hole with less spinning and wheeling. A bike with no cut transmission you wanna gear it for less shifts but a good combination of hole shot and topend. Adding teeth to the front sprocket does the same as less on the rear sprocket.

bcm · « **Reply #3 on:** July 04, 2016, 12:12:27 AM »

Well I'm running 21-11-8 8 paddle haulers, +6 inch swingarm

bcm · « **Reply #4 on:** July 22, 2016, 06:00:51 PM »

I was going to try a 14-36 to see how that does

Sky · « **Reply #5 on:** July 23, 2016, 05:39:36 PM »

IMO I suggest changing one gear at a time. Most say that 3 teeth +/- on the rear equals one gear on the front. If your having problems pulling (seems weird with a 13. Thats small already) go less on the front (12). If is too much go back to the 13 and try like a 39 or 40 on the rear. Good Luck.

bcm · « **Reply #6 on:** July 23, 2016, 11:59:06 PM »

i was running a 13-38 last time I was at sand mountain and it pulled nice up the hill but I noticed it started to lag at the top, I got a 14-36 I'm going to try next month in pismo witch is complete different type of drag racing strip