tire pressures - drag slick

[patrino]

Any suggestions on what tire pressures to run in a 7" drag slick? I'm looking at either the Mickey Thompson ET Drag Motorcycle (26/7.0 x 17"), or the Shinko Reactor II (same size).

Bike is a GS1150-based machine, 8" extended swingarm, wheelie bars, hardtail, stock frame (besides the swingarm).

Looking to fit (and adjust) the wheelie bars; I understand (and it makes sense) that you want to have the tires at track pressures before adjusting them.

Happy to give more details if they'll help with a recommendation.

[Redman]

Bob..... Calling Bob baatfam......

[Baatfam]

There's folks here who know a lot more about racing a small slick bike than I do, and it has been awhile.
But:

Hopefully one of the others can help, but I remember running in the 8-10 psi range. (It's been 12-13 years)
Mines was a bar bike, so no extended swing arm. Meaning it may need to be adjusted from there.

It's hard to see in this photo, but you can see how the sidewall wrinkles. That's what you want.

RT66 Dragbike Series by R John Thieda, on Flickr

[patrino]

thank you for the info, that's a starting point!

wheelie bars vs. no wheelie bars
--AND--
extended swingarm vs. stock swingarm

what's the rule of thumb here for setup? (Assuming the racing club's rules don't have any concrete requirements about what you can and cannot run...)

I've built a few successful road race bikes but never a drag bike. My uninformed thinking is that in general, "longer is better", which makes me think extended swingarm and wheelie bars would be a good way to go. Am I out to lunch?

[patrino]

by the way, @Baatfam, nice photo! Tell me more about the bike, please, if you've got a few minutes ... what engine, frame, etc.?

[stetracer]

It depends on the total weight of your bike. I am at 7.8 lbs on my Pro Et bike with the Mickey. It weighs about 590lbs with me on it.
stay away from the Shinko Slicks. No where near as consistent as the Mickey.

[patrino]

Good info, thanks, I'll be sure to weigh it (and me, with gear) once it's built. Thanks for the warning about the Shinkos, too.

[rapidray]

A safe starting point is 8.0 psi and then go from there as needed.
Ray.

[patrino]

Thanks, Rapidray!

[Baatfam]

Good! I see stetracer and RapidRay are here, so you are in good hands.
I've been out of the game too long to give good advice.

Good luck...And I'll be expected updates.

[red1100]

Patrino, what do you mean by racing clubs rules about concrete? Are you going to be running at PIR, Woodburn, Seattle?

[patrino]

@red1100 - I live 15 minutes from PIR, so plan to be there as often as I can. Woodburn's not too far away, either, but PIR would be my main spot.

[RacingJake]

M/T will hookup 100 times better than a Shinko Reactor II plus the Reactor is a lot harder to install yourself. Took one down to my local dealer and they almost gave up, me thinks they did the hair spray trick to seat the bead.

[patrino]

Ordered up a Mickey Thompson today, thanks everyone.

I took the bike out Sunday afternoon to an industrial area we use for shakedown runs. It's close to my house and abandoned on weekends. Whoa-boy, the bike pulls like semi truck - going to be fun!

[patrino]

New shoe!

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