Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   BMW R1100S / R1200S Tech Forum (http://forums.pelicanparts.com/bmw-r1100s-r1200s-tech-forum/)
-   -   Weighed my 5.5" vs 5", and tire size questions (http://forums.pelicanparts.com/bmw-r1100s-r1200s-tech-forum/24754-weighed-my-5-5-vs-5-tire-size-questions.html)

Markermc 06-14-2001 05:11 PM

Weighed my 5.5" vs 5", and tire size questions
 
Ok, I measured them but they did have tires on them.

The 5" has a 170/60 BT010 Bridgestone and weighs in at 29.5 lbs for the package w/o brake disc.

The 5.5" has a 190/50 MTR24 Pirelli and weighs in at almost 32 lbs for the package w/o brake disc.

What size rear tires do you 5.5-inch-wheelers have on your bikes? I thought normally 180 series? This one has a 190 on it. She's WIIIIDE.

The bike is now short enough that I can sit flat footed to the ground with a slight bend in my knees, and I'm only 5'8" tall!

The flip side is that it changed the gearing enough that with a mild yank, she'll begin to lift her nose now.

Mark
San Ramon CA

CarlosT 06-14-2001 05:26 PM

Kinda blows the Balloonitsky Effect theory eh?

Markermc 06-14-2001 05:30 PM

Guess it does.

They are different brands though, so unfortunately I couldnt compare same brand/different size.

Mark
San Ramon CA

alq2 06-14-2001 08:56 PM

Mark
Yes the standard size for a 5.5 is 180/55/17.
Do you notice any difference in handling?
My guess is that with the back end lower, the steering would slow a bit. Won't go into the extra weight/mass, as that was discussed on earlier posts. Wondering what it does to ground clearance. Smaller diameter should decrease ground clearance, but going wider maybe gets some of it back while leaned over?
Tony

fredman 06-15-2001 03:31 AM

I run a5.5 with a 180 tyre.I run the rear on max preload, and have a (20mm)shorter paralever strut.It made the bike turn much quicker, although a little nervous, so I managed to lower the front (about 6mm) to compenste, and it worked well.It does lift in first & second, (and third if you're hard on it and hit a bump)but handles well.I have a mate who does rider training,and they use R11s's, they run 180 on the stock rim,he says it works ok.you could easily put a 190 on the 5.5.I don't see the need for it, other than asthetics.The bike just puts the power to the ground so well, it would rather lift the front than wheelspin.

Rapt 06-15-2001 04:19 AM

Ummm... Don't you mean raised the front?

As I see it you raised the rear and that made it twitchy, lowering the front is going to make it MORE twitchy, since you're steepening the rake angle still more.

Its also worth noting that moving the fork sliders up/down doesn't change the geometry on this bike.

I am curious though as to how/why the larger tire causes the front to come up eaiser... does it have a smaller outside diametre?

[This message has been edited by Rapt (edited 06-15-2001).]

Markermc 06-15-2001 05:42 AM

Yes it is a shorter tire.

180/55... 55% of 180(mm?) is the height of the tire from bead to tread (something like that if I'm not stating it exactly) which equals 99

190/50... 50% of 190 equals 95 - shorter tire

170/60... equals 102 - a taller tire

Therefore we see that the aspect ratio allows you to determine roughly the variations between tire sizes.

Class dismissed.

Mark

turnerm 06-15-2001 06:19 AM

Doesnt the extra rubber wiegh more? Just a hunch.

Im surprised a 190 fits on the bike.
I thought the 180 barely clears the rear drive.

Rapt 06-15-2001 06:27 AM

Gotcha. I knew the number was the sidewall height in percentage of width... I just hadn't bothered to actually work it through.

But it is obvious... Once you point it out... http://www.pelicanparts.com/ultimate/smile.gif

CarlosT 06-15-2001 07:30 AM

Quote:

<font face="Verdana, Arial" size="2">Originally posted by Markermc:
Yes it is a shorter tire.

180/55... 55% of 180(mm?) is the height of the tire from bead to tread (something like that if I'm not stating it exactly) which equals 99

190/50... 50% of 190 equals 95 - shorter tire

170/60... equals 102 - a taller tire

Therefore we see that the aspect ratio allows you to determine roughly the variations between tire sizes.

Class dismissed.

Mark
</font>
Tell that to Mr. Dunlop. He likes his tires BIG.


Markermc 06-15-2001 12:33 PM

I suspect its a combo of the wider rim and to a larger degree the bigger tire that adds to the weight difference.

The rear drive is cleared just fine on mine by the 190. Has about 3/8" clearance and shows no signs of rubbage...

I will likely go back to the 180 after this tire. I wouldve had one on it to begin with, just the p.o. had a 190 on it, so I inherited the rim that way.

Mark
San Ramon CA

fredman 06-16-2001 03:13 AM

I lowered the front by shortening the rubber bushing on top of the shock, effectivly shortening the shock lenght. The did not steepen the steering-quite the opposite, because of the angle of the telelever (or front swingarm if you like).It brought the front a-arm closer to paralell with the ground.This gives it more rake, and settled the bike down.It still turns sharper than stock.I didn't move the sliders at all.

jclark 06-16-2001 10:02 AM


Previous in time, CarlosT caused electrons to form:

&gt;Tell that to Mr. Dunlop. He likes his tires
&gt;BIG.

It's true –*my friend has 207 @180 and I Pilot Sport@180, und he has a MUCH BIGGER, um, radius, looking from the backside. Also measures that way, by about 3/4"(19.05mm)

Bigger is better, baby!

j


All times are GMT -8. The time now is 12:22 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.