Smaller Diameter Front Wheel?

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Frank
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Smaller Diameter Front Wheel?

Post by Frank »

1976 GT550 - I'm drag racing; someone told me Suzuki had a 16" front wheel that might work on this bike but I don't have a clue about how to try to find one. Going from a 19" to a 16" would drop the front quite a bit which would be a good thing. Any ideas or hints appreciated!

thanks,
Frank
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Re: Smaller Diameter Front Wheel?

Post by yeadon_m »

Frank,
No idea on wheel source, and also I'm not an expert, but wouldn't such a change produce an undesirable change in steering geometry? (by altering the angle of the steering head). I fear it would render a fast steering front end, and if so, quite the opposite of what you'd wish for in a drag bike? Maybe its the other way around....like I said, I'm no expert!
Cheers,
Mike
Frank
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Re: Smaller Diameter Front Wheel?

Post by Frank »

Hi Mike,

With this one change alone, what you say is true (changed geometry), however, the seat tubes have been cut down and it's a hardtail and the rear is lowered quite a lot already. The fork tubes are stuck through the triple tree as much as I dare and I'd risk a bit of instability to get the front a bit lower. Worst case: I could rake out the front end a bit although I don't think that would be necessary. Maintaining good brakes is my largest concern. :)
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tz375
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Re: Smaller Diameter Front Wheel?

Post by tz375 »

Are you restricted to a period correct wheel or a SUZUKI (same manufacturer) wheel by the rules? If not, check out any modern 125 or 250 for a narrow 17" wheel and disk and maybe pick up the whole front end to swap in.
Frank
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Re: Smaller Diameter Front Wheel?

Post by Frank »

No restrictions: I've never done any front-end swaps but that's a good idea i.e. swap in the whole thing. What's the best procedure: get the triple trees and everything, then try to find appropriate size bearings?
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Re: Smaller Diameter Front Wheel?

Post by smokin_blue »

Frank,
I was struggling to remember any Suzuki that ran a 16" front rim but a simple google and ebay search corrected my memory. I found both the GS550E from 1983 and the GS1150E from 1984 did. This would be right as the '83 timeframe was when the industry was hooked on small front wheels. It lasted only a short time. The went essentially from 19's to 18's to 16's back up to 18's and and finally settled on the 17's of today. If you want a narrower front rim focus on the GS550 range, if you want wider go for the bigger bikes. That said these were all mag and run disc brakes so if you are running no front brake on your dragster you are fine. If you want brakes you might need a fork change too.

http://www.ebay.com/itm/like/1415958918 ... =82&chn=ps" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

on your thoughts though I was wondering why smaller. Most dragsters go larger but then rake out the front end. Both give you more stability.

1. The larger front wheel handles surface irregularities better
2. a smaller front wheel will give you less trail - larger wheel would be better with more trail
3. raking it out gives you both rake and trail both of which will lead to better high speed stability.

If you decide to go larger then you can find some 21" in the early intruder line that would probably bolt right in other than maybe an adjustment on spacers.

PS: a larger front wheel will add rake and trail by default as well as you slamming the rear end. Hence your easiest approach might be to go to a 21" front rather than a 16".

If you want the front end physically lower you can limit the travel on your forks and pull them up as short as possible in the triples clamps.
'07 Suzuki SV650
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tz375
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Re: Smaller Diameter Front Wheel?

Post by tz375 »

All good info but larger wheels handle bumps and dips better because they have less of a tendency to drop into the hole.

Drag bikes usually run 18" 3210 2.5/2.75-18 ET Drag Front Slick on a relatively narrow 18" rim. If you don't need a slick, try http://www.ebay.com/itm/2001-01-Kawasak ... 1304882539" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false; It appears to be 16 x 2.15".

Or try this http://www.ebay.com/itm/Suzuki-GN125-Ca ... 19ffdef992" onclick="window.open(this.href);return false;

Or take a stock GT disk hub and lace it up with an aluminum rim and single later model disk - light and not too expensive.

Bridgestone do a 90/90 18 front BT45

Avon offers an 80/90 race compound front or a 90/90-19

Choose the front tire/wheel combo to lower the front end, then lower the back end with shorter stiffer shocks to get the rake back and go have some fun.
Frank
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Re: Smaller Diameter Front Wheel?

Post by Frank »

Great ideas, Gents! Thanks so much for taking the time to respond, You've given me lots to think about!
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