GS1150 drag-racing baseline gearing recommendations

[patrino]

Looking for baseline / starting-point gearing recommendations - any suggestions?

Bike is an '85 GS1150, I believe internal primary drive and transmission ratios are stock. Looking to get recommendations for both 1/8-mile and 1/4-mile setup.

I know I'll need a giant pile of sprockets eventually ... just looking for some good starting points for both track-length setups.

Any suggestions appreciated!

Thanks, Patrick

[kingofvenus]

Mine is set-up to hit my shift point (when shift light comes on) in forth gear at the start of the traps in the 1/4. I don't change it for any 1/8 mi races. I'd start with stock and go from there after you make a bunch of passes.

[RacingJake]

GS1100E run's 14/46 on a 630 chain with M/T 7" slick, small shot of nitrous it hits the rev limiter at 10400 right pass the 1/8 mile in 4th gear. I shift at 10K.

You can hear it here

https://fb.watch/1wx7JQGpUh/

[trippivot]

stock engine will run out like a wild cat with a 14-49-48-47 and get to top of 5th gear at redline. -- but you are going to wheelie off of the line. wheelie bars 68" wheelbase suggested for that approach..

next choice is almost stock 15-47- 46 maybe 45 and your launch will be manageable

[patrino]

I appreciate the info!

[stetracer]

My stock wheel base no bar 1150 went 9.72@146mph 17/48 530 gearing. Which is the same as stock gearing.
No problems with the wheelie’s but I was using a MTC slider clutch.
I agree with Trip a 15/45t or 47t rear would be pretty gearing for stock wheel base stock motor. IMO

[patrino]

phatty_mcwheelerton.jpg

Thanks again for the additional info! The bike came with an ~8" over swingarm with the spares (I think it's Trac Dynamics). I replaced the stock swingarm last month. A buddy made an axle for me and I built wheel spacers and a caliper carrier last week. I don't have an overall wheelbase measurement, but it's ~36" center-to-center from the front sprocket to the rear axle (I wanted that number to figure out chain length).

I also fit the 5.5" rear wheel I got, to replace the 3.5" stocker that was in it before.

Will need to adjust the wheelie bar cross-braces to work with the longer swingarm.