Landracing Forum

Bonneville Salt Flats Discussion => SCTA Rule Questions => Topic started by: coloradodave on September 14, 2009, 02:18:56 PM

Title: Motorcycle Tires
Post by: coloradodave on September 14, 2009, 02:18:56 PM
We are trying to find in the rule book whether or not we can run a front tire on the rear of our bike, the tire has the correct date codes and speed rating.
Any help would be much appreciated.
Thanks Dave
Title: Re: Motorcycle Tires
Post by: Dakzila on September 14, 2009, 05:17:17 PM
Just my two cents worth....

I've seen some bike at El Mirage with front wheels on both ends....

I've also reviewed the rule book in answer to this same question and have not found where it would be against the rules.

I have noticed some manufactures state their front wheels should not be used as a drive wheel.....so I'd keep that in mind..

What's your application and why would you want to run a front wheel on the rear?

Let's see what the knowledgeable players say about this.....

Buzz
Title: Re: Motorcycle Tires
Post by: k.h. on September 14, 2009, 05:35:34 PM
It's the only way to get a VR rated 19-inch tire on the rear, probably.  For limited use, should be okay.  The question is what happens to the cross-layered belting inside if it is turning and flexing opposite to design.  Or, go with 18-inch on the rear for better availability.  What will raising the rear of the bike do for steering without compensating in the front rake and trail?
Title: Re: Motorcycle Tires
Post by: coloradodave on September 14, 2009, 05:39:09 PM
We are running a narrower tire on the front and in trying to save some money we could also run narrower on the rear by using our current front set up on the rear, the front hub is drilled and tapped on both sides with the same hub diameter as the sprocket.
Thanks for the reply.

Dave 
Title: Re: Motorcycle Tires
Post by: coloradodave on September 14, 2009, 05:41:19 PM
We used to run rear tires on the front of custom bikes, we would reverse the rotation and they worked great.
Title: Re: Motorcycle Tires
Post by: willieworld on September 14, 2009, 05:59:17 PM
i build a lot of neo-classic bikes (they look classic but are made from new parts )  i had the harley shop call the tire reps and ask them if i could run a front tire on the rear---the rep said that if the tire has a arrow on it and you mount a front on the rear the arrow should point the wrong way---the reason is the stress on the front tire is from braking and the stress on the rear tire is from power applied---it has to do with the way the tire is built---some tire folks are making tires with 2 arrows now one for front fitment and one for rear fitment ---the tires i use front and rear are 90  90  21s   -------avon roadrider  rated v----------willie buchta
Title: Re: Motorcycle Tires
Post by: k.h. on September 14, 2009, 06:11:47 PM
Yeh, I forgot to say it's likely best to run the front tire backwards on the rear.  For the track only.  If you run on the street and have an accident, the other party's investigator may see the rear tire running backwards and use it as a reason to blame things on you.
Title: Re: Motorcycle Tires
Post by: sockjohn on September 14, 2009, 06:25:17 PM
I remember the SCTA or ECTA made a ruling against the 2.5x17 front runners as rear tires.

Not a bike tire, but might be worth looking into WHY they made this decision (weight?)

Might also be worth running your question by the appropriate tech person.
Title: Re: Motorcycle Tires
Post by: willieworld on September 14, 2009, 10:11:33 PM
A picture is worth a thousand words.
Willie Buchta
Title: Re: Motorcycle Tires
Post by: coloradodave on September 16, 2009, 01:39:51 PM
The tire we will be using has a smaller circumference than the on we used last year,that will increase the rake a little bit.
Thanks for all of your input. :-D
Title: Re: Motorcycle Tires
Post by: willieworld on September 16, 2009, 02:10:14 PM
the ruleing was not to let the tire be run on the drive wheel (s) not on the rear --if you have front wheel drive you could run them on the rear -------------------willie buchta
Title: Re: Motorcycle Tires
Post by: coloradodave on September 16, 2009, 03:50:03 PM
Thank you very much, we will try something else I guess, I appreciate everyones input. 
Title: Re: Motorcycle Tires
Post by: Dakzila on September 16, 2009, 07:42:06 PM
 :wink:Front wheel drive motorcycle Willie?     :cheers:
Title: Re: Motorcycle Tires
Post by: 1212FBGS on September 16, 2009, 09:29:46 PM
not legal or smart..... read the rule book!
kent
Title: Re: Motorcycle Tires
Post by: willieworld on September 16, 2009, 09:49:47 PM
i was talking about cars for front wheel drive---all motorcycles rear drive front steer only ---willie buchta
Title: Re: Motorcycle Tires
Post by: Seldom Seen Slim on September 16, 2009, 10:02:33 PM
Willie, isn't there a Rokon (or something like that) that's two-wheel drive?  Big tires and built for off-road use -- with hydraulic front wheel drive.  Not a race bike, though. . .
Title: Re: Motorcycle Tires
Post by: Stan Back on September 16, 2009, 10:23:08 PM
With some salt conditions it could be a good idea.

Stan
Title: Re: Motorcycle Tires
Post by: Dakzila on September 17, 2009, 12:39:08 AM
Seldom.

Correctomundo...Rokon with a belt drive front wheel....if I remember correctly....

Buzz
Title: Re: Motorcycle Tires
Post by: 46champ on September 17, 2009, 10:27:00 AM
Rokon's have a chin front drive both ends are duplicates of each other.
Title: Re: Motorcycle Tires
Post by: Glen on September 17, 2009, 10:31:18 AM
Can you get it with traction control??? :roll:
Title: Re: Motorcycle Tires
Post by: sockjohn on September 17, 2009, 11:09:09 AM
FWIW, there are kits to do this for dirt bikes.

http://www.christini.com/index.php

Review here:
http://www.motorcycle-usa.com/20/262/Motorcycle-Article/2007-Christini-AWD-Quick-Ride.aspx


Track test of an R1:
http://www.motorcycle-usa.com/269/4240/Motorcycle-Article/Yamaha-R1-Ohlins-2WD-Review.aspx

Title: Re: Motorcycle Tires
Post by: coloradodave on September 17, 2009, 12:26:37 PM
I've been racking my brain all morning trying to think of Christini, Thanks. :?