ADVrider

ADVrider (http://www.advrider.com/forums/index.php)
-   Parallel Universe (http://www.advrider.com/forums/forumdisplay.php?f=77)
-   -   18" Rear wheel on an 800GS (http://www.advrider.com/forums/showthread.php?t=516569)

never.ride 10-17-2009 08:51 AM

18" Rear wheel on an 800GS
 
I know this has been talked about it a little, but I can't track down the threads for it. Has anyone done it? Anything you need to change to make it happen? Any other advantages besides tire choice?

I had Woody's do my front wheel and it is totally bomber. Thinking I may have them do the same on the rear with an 18" for more tire choice, etc.

Thanks guys!!

johngil 10-17-2009 08:00 PM

The 18" tires I know of seem too tall. I will be going to a 17" x 3.5" rim this week so that I can use a 130/90 tire. There are quite a few choices in this range and the OD is a close match.

Bartron 10-18-2009 11:26 AM

1 Attachment(s)
I have been thinking about this mod for a long time. I'm not convinced there would be clearance issues. I'm running 140/80 17 and have at least 2.5 inches of clearance at the swingarm. The wheel could also come back another half-inch with a longer chain. The Bitubo/Twalcom race bike has 18" Excel's mounted but detailed info on that bike seems unobtanium.

An additional consideration is ABS. For those of us with ABS bikes the computer may think that the rear wheel is locking us as it would be spinning slower than a 17". Would love to hear if anyone has encountered this or heard of a fix (besides ordering the bike without ABS). the 140/80 I put on instead of the 150/70 has a greater circumference than stock and that has not had any effect but I could just be within some sort of acceptable range.

Bartron 10-18-2009 11:30 AM

1 Attachment(s)
Here's another shot. BTW, that fender eliminator is lovely and I wish I could find one. :tb

johngil 10-18-2009 12:00 PM

Is anyone sure the front and back ABS channels are linked in any way?

Since I need to get my new wheels laced up this week, I will stay on the safe side and stay w/ the 17" rim. At least I will be able to use the stock spokes and save a few bucks if I go 17" x 3.5" If a 2.75" x 17" is used, then I'll need new spokes.

What size 18" tire would be used?

Bartron 10-18-2009 12:37 PM

Quote:

Originally Posted by johngil
What size 18" tire would be used?

Would love to run 140/80-18 as well as have option for 130/80, 130/90 and 140/90. The tires are also SO much cheaper for the 18 inch rims. Would recover the cost of the rim within one year easily.

johngil 10-18-2009 12:46 PM

The 140/80-18 tires I have seen (908RR) seem HUGE. Yet they are only an inch taller than the 606 in 130/90-17 when comparing on the Dunlop website. Dunlop lists a 150/70-17 (607) as 25.25". The 130/90-17 (606) as 26.30" and the 140/80-18 (908) as 27.25".

I'm finding lots of 130/90-17 and 140/80-17 tires available and some for a good price. I agree about recovering costs in a short while.

mousitsas 10-18-2009 04:22 PM

Quote:

Originally Posted by Bartron
An additional consideration is ABS. For those of us with ABS bikes the computer may think that the rear wheel is locking us as it would be spinning slower than a 17". Would love to hear if anyone has encountered this or heard of a fix (besides ordering the bike without ABS). the 140/80 I put on instead of the 150/70 has a greater circumference than stock and that has not had any effect but I could just be within some sort of acceptable range.

I think that the ABS computer cares about rates of decceleration of the wheels and not their absolute speed. If this is true, then it won't make any difference whatever the wheel size.

Bartron 10-18-2009 04:53 PM

Quote:

Originally Posted by johngil
The 140/80-18 tires I have seen (908RR) seem HUGE. Yet they are only an inch taller than the 606 in 130/90-17 when comparing on the Dunlop website. Dunlop lists a 150/70-17 (607) as 25.25". The 130/90-17 (606) as 26.30" and the 140/80-18 (908) as 27.25".
I had a look as well. The stock BattleWings in 150/70-17 have an OD of 25.4" while the 908RR in 140/80-18 has an OD of 27.24" as you mentioned. Leaving a difference of 0.85" in axle height which shouldn't cause any clearance issues with swingarm and shouldn't affect geometry by much.

I'm finding lots of 130/90-17 (did you mean 18" for both?) and 140/80-17 tires available and some for a good price. I agree about recovering costs in a short while.

Yay! This is looking ever more likely!

johngil 10-18-2009 05:04 PM

I am finding 130/90-17 and 140/80-17 in several different brands. I'm going w/ 17" for now.

bxr140 10-18-2009 05:39 PM

FWIW, I would NOT want a 130 on the back of my 800. WAAAAYYY to skinny for the weight and power.

johngil 10-18-2009 06:07 PM

The #'s from the tires I have looked at in 130 will carry the weight.
I think I would rather have a 130/90 606 Dunlop over a 150/70 TKC in the soft stuff. We'll see. I'm finding quite a few 17" in 140/80 as well.
I don't think the +/- 3/8" in width is going to kill me between the 130 and 140. The big KTM's are on 140's and pump out quite a bit more horsepower and weigh more.

la fletche 10-18-2009 07:40 PM

Google Wunderlich BMW and you will find what you are looking for.

johngil 10-18-2009 08:25 PM

Quote:

Originally Posted by la fletche
Google Wunderlich BMW and you will find what you are looking for.

Didn't help me. But thanks.


Times are GMT -7.   It's 06:16 AM.

Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014