The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: mikethebike on July 11, 2008, 11:50:17 AM

Title: 4.00 x 18 alternative tyres?
Post by: mikethebike on July 11, 2008, 11:50:17 AM
I have a 4.00 x 18 tubed rear tyre which I will soon change.  There are few of this size available. I understand that 110/90 is the metric alternative and that size has a bigger range of options.  Any comments on use of these please?
Title: Re: 4.00 x 18 alternative tyres?
Post by: Ed Miller on July 11, 2008, 12:48:32 PM
The 110s are what I use.  They fit fine, may not be the same diameter as the 4.00.  I've never checked.

Title: Re: 4.00 x 18 alternative tyres?
Post by: crazy_dan on July 11, 2008, 01:06:24 PM
myself, i run the 4.00-18 metzler me-77, and i get enough tread out of them to burn the sides off a pair of shoes by leaning it so far, and i've never had any problems with traction in the rain or even snow for that matter. [smiley=3stooges.gif]
Title: Re: 4.00 x 18 alternative tyres?
Post by: montmil on July 11, 2008, 01:35:02 PM
Quote
... Any comments on use of these please?

Just this past weekend, I mounted a set of Bridgestone S11 Spitfire tires.  My R65 had a Metzler 120/90 on the rear that just barely cleared the driveshaft housing. No rub marks on the chassis but it was a booger-bear to get off for service.

The Bridgestone rear I mounted is a 110/90 and I'll be danged if I can see much difference in the tire width. I'm sure it's there and I still have to deflate the tire to fit and remove. I'm running the Bridgestone tubeless as was the old Metzler. Spent some quality time cleaning the interior of the rim.

Here's a page from webBike World about tires and their actual dimensions when comparing different tire sizing standards. I found the info very helpful.

http://www.webbikeworld.com/Motorcycle-tires/sizes.htm
Title: Re: 4.00 x 18 alternative tyres?
Post by: Semper Gumby on July 11, 2008, 03:46:13 PM
I have had the Macadam 120/90H18 on the back with no rubbing.  I currently have an Avon Roadrider 4.00V18 with which I am quite happy.  When the Avon is done I might go back to the Macadam in the 4.00H18 and see if it handles as well as the Avon.  Time will tell..
Title: Re: 4.00 x 18 alternative tyres?
Post by: montmil on July 11, 2008, 03:56:24 PM
Here's a recent thread from the "Rants" section regarding tires. Quite informative.

http://suraklyn.com/yabb/YaBB.pl?num=1213794434

Title: Re: 4.00 x 18 alternative tyres?
Post by: Justin B. on July 11, 2008, 05:45:58 PM
I have used the metric sizes for years and use the 110 on the rear and 90 on the front...
Title: Re: 4.00 x 18 alternative tyres?
Post by: Rob Valdez 79 R65 on July 11, 2008, 07:15:44 PM
Quote
The Bridgestone rear I mounted is a 110/90 and I'll be danged if I can see much difference in the tire width. I'm sure it's there and I still have to deflate the tire to fit and remove.
I use the same rear tire, and I have to do the same thing...  :(


Quote
I'm running the Bridgestone tubeless as was the old Metzler. Spent some quality time cleaning the interior of the rim.

If you wouldn't mind, please start a new thread about how you converted your snowflakes to tubeless, and elaborate on your experiences so far.

Thanks!
Title: Re: 4.00 x 18 alternative tyres?
Post by: mikethebike on July 12, 2008, 04:47:01 AM
When I replaced my front tyre, I had a heck of a job getting the tube in.  The shape of the wheel made it extremely difficult and I was wondering about going "tubeless".  I suppose it's a bit like the ladies going bra-less!  You just need that bit of confidence in your equipment!
Title: Re: 4.00 x 18 alternative tyres?
Post by: montmil on July 12, 2008, 07:52:51 AM
Quote
... I was wondering about going "tubeless".  I suppose it's a bit like the ladies going bra-less!  You just need that bit of confidence in your equipment!

Too funny!  We need Jon P's avatar posted here. You know the one...  lol [smiley=beer.gif]
Title: Re: 4.00 x 18 alternative tyres?
Post by: montmil on July 12, 2008, 08:11:51 AM
Quote
If you wouldn't mind, please start a new thread about how you converted your snowflakes to tubeless, and elaborate on your experiences so far. Thanks!

I personally did not "convert" to a tubeless rear tire. When I purchased the bike, I noticed there was a tubeless valve stem in the rear and a conventional inner tube valve poking through the front rim.

Both Metzler tires were vintage and showed it with cupping, cracks and checking all around. I was unwilling to ride the bike with tires in such shoddy condition. I posted a tire query in "Rants" which generated much helpful advice.

http://suraklyn.com/yabb/YaBB.pl?num=1213794434

Stayed with a tube in the front tire and, yes, the rim shape makes installing the tube a bit of an S-M chore. No pinching, boys!

After removing both Metzlers, the interior of both rims were grimy and dirty. There were a couple aluminum "spurs" which I attributed to tire spoons or, heaven forbid, screwdrivers. Dressed these with a small diemakers mill file. Simple Green and a ScotchBrite got the interior looking good. After a rinse and drying, tires were mounted.

Would appear that the rear tire was running tubeless for quite some time as years-old service records that came with the bike included the repair of a flat on the rear tire. I even found the tire "plug" poking into the tire's interior.

So I went with the old axiom If it ain't broke, don't fix it for staying tubeless on the rear tire. I do strongly recommend a smooth, clean rim for the tire bead. Both ends of the bike, actually.

 
Title: Re: 4.00 x 18 alternative tyres?
Post by: Altritter on July 12, 2008, 10:49:29 AM
My '81 had a Metzler 120/90 on the rear when I purchased it. It clears, but the difference in the profile *might* contribute to the front tire's not clearing the ground when the bike is on the center stand. I haven't done a detailed check of the center stand yet. It works OK, but I do notice the bike having a slight lean to the right (from riding perspective), or "off" (in equestrian terms) side. Not dangerous at the moment, but maybe I should have it checked.

I noted a posting on this forum regarding not changing factory configuration without good reasons. I tend to agree. Nonetheless, there are numerous comments on the Web (Noemi Berry's articles circa 1995 come to mind) recommending 120/90s, even if a spacer is required. In my particular case, I'm inclined not to fix something that isn't broken yet.

Incidentally, my mindset on tires applies to the shorter-shock modification, also. With my bike, I can flatfoot with a bit of stretching to get my heels on the ground. I wasn't certain whether my shocks were standard or short until I was able to compare. Bob's BMW (Jessup, MD) currently has a '79 Bronco R65 for sale with the shorter shocks. I sat on it and found it much more comfortable, i.e., mine are standard. Nonetheless, I'm reluctant to change because (1) my current shocks are Koni, and (2) I have no way of knowing how the shorter shock travel and lower frame configuration might affect ride and handling.

The other height modification, lowering the seat, seems to require some additional compromises. Anyone out there found a seat modification that would not break either my bank account or tailbone (or both)?
Title: Re: 4.00 x 18 alternative tyres?
Post by: Jon_P on July 14, 2008, 10:16:49 AM
here is my avatar to this thread  ;D
Quote
I suppose it's a bit like the ladies going bra-less!  You just need that bit of confidence in your equipment!

i am running a 120 in the rear and there isnt much room but enough for tire to heat up and expand. a 130 there isnt enough room for in the rear. i thought about relacing the rim with a offset so i could run a bigger 130 but never got to it yet.
Title: Re: 4.00 x 18 alternative tyres?
Post by: Ed Miller on July 14, 2008, 11:19:18 AM
This is weird.  Rob and Brother Miller both have the same rear tire I do, a Bridgestone S11 Spitfire 110, and both have to deflate the tire to install or remove it.

I don't.  I wiggle it in or out; the brake shoes have enough play that I can push or pull past them without hurting anything.  I do get the rear pretty high up in the air by setting the bike up on the center stand on top of a chunk of 4 x 12, maybe that's why.  A bike life with a drop out for the rear wheel would serve the same purpose and be easier.  
Title: Re: 4.00 x 18 alternative tyres?
Post by: montmil on July 14, 2008, 01:10:17 PM
Quote
This is weird.  Rob and Brother Miller both have the same rear tire I do, a Bridgestone S11 Spitfire 110, and both have to deflate the tire to install or remove it. I don't.  I wiggle it in or out; the brake shoes have enough play that I can push or pull past them without hurting anything.  I do get the rear pretty high up in the air by setting the bike up on the center stand on top of a chunk of 4 x 12, maybe that's why.  A bike life with a drop out for the rear wheel would serve the same purpose and be easier.  

I get my R65 up on a 1.50-inch plywood pad but it's not high enough to "drop" the tire out. I use a small ramp to assist in getting the centerstand down. A 4x12? Ed, I do not want to ever get in an arm wrestling contest with you! You da man! Gonna nickname you "Arnold" or "Conan"   8-)

Rear tire removal is a chore... what with rubbing the brake shoes and snagging the tire on the flexible - thank goodness - rear fender.
Title: Re: 4.00 x 18 alternative tyres?
Post by: Rob Valdez 79 R65 on July 14, 2008, 10:37:28 PM
I get plenty of work space, as I remove the front wheel and tip the bike on the front forks.  (after securing the centerstand - yadda yadda yadda...)


It's still just really tight between the two sides.  I wonder if my left side of the swingarm has somehow been bent inward, like, say, if a dummy (me) were to tighten the clamp on the axle before tightening the big axle nut.  
That would pull the left side over, and over time, might close the distance.
Title: Re: 4.00 x 18 alternative tyres?
Post by: montmil on July 15, 2008, 06:59:16 AM
Quote
This is weird.  Rob and Brother Miller both have the same rear tire I do, a Bridgestone S11 Spitfire 110, and both have to deflate the tire to install or remove it. I don't.  I wiggle it in or out; the brake shoes have enough play that I can push or pull past them without hurting anything.

Besides the rear brake shoes and the fender interference during wheel removal, the lower mounting bolt on the left shock absorber also rubs on the tire's sidewall. This just adds to the degree of difficulty. Thankfully, rear tire removal is not on my weekly maintenance list.