Landracing Forum

Bonneville Salt Flats Discussion => SCTA Rule Questions => Topic started by: Anchor on April 16, 2012, 12:35:47 AM

Title: Help on drag tires for MC Bike
Post by: Anchor on April 16, 2012, 12:35:47 AM
I'm entering a lil'moped in the A/G 100cc class and need H rated tires 2.5X17 front
and rear, anything wider would hit the drive chain, I was looking at the
Goodyear D1445 front runner drag tires, and a little confused if these would pass
tech inspection, any advice would be appreciated. I'll try and post a pic.
Title: Re: Help on drag tires for MC Bike
Post by: Dakzila on April 16, 2012, 07:49:05 PM
What venue are you building for?

What is the A/G 100cc record at the location you'll be running?

Buzz
Title: Re: Help on drag tires for MC Bike
Post by: Anchor on April 16, 2012, 08:05:33 PM
The venue is Bonneville Salt Flats , The A/G Record is 99mph.
I have S rated tires (113mph) but was told I need an H rated tire
by one of the officials.  I don't see any written rules in the 2012 book, but
read on a forum that the Goodyear drag tires cannot be used on rear wheels,
still waiting on confirmation.  I saw a hoosier tire 2.5 X 17 but I imagine they
might not pass either for a rear.  I have seen some 17's rated H but none so
far will work on these moped rims.  Any advice ???
thanks
-Todd
Title: Re: Help on drag tires for MC Bike
Post by: sabat on April 16, 2012, 08:27:02 PM
I wonder if a slick from the front of a 125cc road race bike would be skinny enough?
Title: Re: Help on drag tires for MC Bike
Post by: Anchor on April 16, 2012, 08:35:03 PM
I researched 125gp tires but they seem a bit too wide. Plan B is switching to a
18" rear, Emot racing have some 2.25/2.5's x 18 H Rated, then just use the
goodyear drag for the front 17"...
Title: Re: Help on drag tires for MC Bike
Post by: BHR301 on April 16, 2012, 10:31:22 PM
I may be missing something...but as I read the rules..you can't run a tire designed as a drive tire for a drag race vehicle (a drag slick) but I found nothing saying you can't run something like the GoodYear front runner on the back of your bike. I just checked and the BUDDFAB streamliner is using GoodYear front runners both wheels..

Bill
Title: Re: Help on drag tires for MC Bike
Post by: Dakzila on April 17, 2012, 11:13:18 AM
I'll research it a little more but I'm sure you're OK with an S-rated tire for a class record under 100 MPH.

Buzz
Title: Re: Help on drag tires for MC Bike
Post by: Anchor on April 17, 2012, 11:58:39 AM
Thanks Buzz !,   I emailed Matt Shuss about the S tires but he said anything under H is not recognized and would
put the S rated tire at 70mph limit.  I realize that it a safety concern but was a little confused by the fact that
the rule book states your tires should be rated to the record in the class, I guess the two rules run together when
it comes to checking the ratings. I'm might try the Goodyear front runners put I'm concerned they may not fit
my rims properly...more research...

-Todd
Title: Re: Help on drag tires for MC Bike
Post by: Dakzila on April 17, 2012, 05:03:05 PM
Well Matt is the final say!

I've used the Front Runners on 1.85 rims with no problems.

You might also check out Avon Speed Masters.  I have a set of Avon Speed Master 275/300X19" on my bike and I'm running a WW1 rim.
Not sure if Avon sales a 17" Speed Master but it 's worth checking.

Good luck,
Buzz
Title: Re: Help on drag tires for MC Bike
Post by: Anchor on April 17, 2012, 07:33:32 PM
The tires currently on the bik are 80/90-17", how would you compare
the width on the good year front runners is it actual 2.5 width?
The max width I could probably go is 2.75. Appreciate all the info!
-Todd
Title: Re: Help on drag tires for MC Bike
Post by: Dakzila on April 17, 2012, 07:36:04 PM
Check out the Bridgestone Battlax H rated bias series.
There's a 100/80-17H tubeless tire that fits on a 1.85 to 2.75 rim.  These are front tires but you could run a front on the rear. Maybe these will fit.

Here the link to the Bridgestone page:  http://www.bridgestone.com/products/motorcycle_tires/products/battlax/bt39.html

BT-39 Front tubeless H rated
TIRE SIZE REC. RIM (inch) MEAS. RIM (inch) OD (mm) TW (mm)
  
  100/80-17M/C 52H TL 2.50 1.85 - 2.75 594 101  
  110/70-17M/C 54H TL 3.00 2.75 - 3.00 587 108
  110/80-17M/C 57H TL 2.50 2.15 - 3.05 614 113


Buzz
Title: Re: Help on drag tires for MC Bike
Post by: Anchor on April 17, 2012, 09:47:45 PM
All these tires are good options but I just heard back from the rules chair...
"Any tires that are specifically constructed for “front fitment” only would not be allowed to be used as a drive tire."
Title: Re: Help on drag tires for MC Bike
Post by: saltwheels262 on April 17, 2012, 09:56:00 PM
sure seems to be a lot of front runners on the rear.
Title: Re: Help on drag tires for MC Bike
Post by: Dakzila on April 18, 2012, 11:15:32 AM
All these tires are good options but I just heard back from the rules chair...
"Any tires that are specifically constructed for “front fitment” only would not be allowed to be used as a drive tire."


Lots of smaller bikes are currently running front drag tires on both ends???????

Buzz
Title: Re: Help on drag tires for MC Bike
Post by: Stan Back on April 18, 2012, 11:45:36 AM
I don't know (as most of you well know), but are these tires marked "front"?  If not, how can they be excluded as drive tires (for a wheel-spinning at 200 MPH 100cc open bike)?
Title: Re: Help on drag tires for MC Bike
Post by: FirePowerMinis on April 18, 2012, 04:42:24 PM
I'm getting a batch of 50/100, 60/90, 70/90 17" H-rated skinnies just for us lil zingers. Prolly not for a month or so, though.
Title: Re: Help on drag tires for MC Bike
Post by: Anchor on April 18, 2012, 09:26:14 PM
^that's good news, email me and I'll buy a set if your selling.

-Todd