Rimming

As it says; what you've done to your bike and how it helped make it better.

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austinpowers
Posts: 9
Joined: Tue Jun 23, 2015 11:22 pm

Rimming

Postby austinpowers » Tue Apr 26, 2016 6:42 pm

My 11S has the five inch rim. Looking at it next to another machine with a five inch, the S appeared to be wider all round. Out came the Verniers, and measured across at the narrowest gap (to match where the tyre rim is seated) I came up with a digital read out of 5.55 inches, seemingly contradicting the claim stamped on the hoop itself....

But this is by no means unique. The bike next to it, my ZRX, also allegedly had a 5 inch rim but in fact measures 5.33 inches and takes a 180 section (Metzeler) pretty comfortably if required. Different 180s (or any other section) may vary considerably from make to make.

So before anyone rushes off to find the 5.5 inch rim (to accomodate 180s) measure up first. You never know. If you're closer to 5.5 than 5.0 you're in the ballpark.

Scotland
McBoxer
Member
Posts: 475
Joined: Wed Jul 11, 2012 2:53 pm
Location: West Midlands

Postby McBoxer » Wed Apr 27, 2016 9:35 am

Interesting. I'm pretty sure the rim width measurement should be taken between the inner seating faces - ie, where the bead sits inside the wheel - so I would expect the outside of the wheel to measure wider. How much wider will depend on the design / material of the wheel of course.

Does this picture match the measurement you took?

Image
Big Scottish Al
____________
1982 BMW R65LS
1̶9̶9̶9̶ ̶B̶M̶W̶ ̶R̶1̶1̶0̶0̶S̶
1998 BMW Z3
2004 BMW X3

England
SP250
Posts: 670
Joined: Mon Sep 09, 2013 2:01 pm
Location: North Shropshire

Postby SP250 » Wed Apr 27, 2016 12:00 pm

The 5" 1100S rim will accept a 180 section tyre but it pulls the beads inwards and therefore the profile is out of shape.
It reduces the width of the contact patch and makes the shoulders curve inwards also reducing the patch when leant over.

I have run both 180 and the correct 170 section tyres on the 5" rim and the difference was quite marked.
Bike was much nicer on the 170 and less "nervous" at the rear but also steering more positively. Tyres are cheaper too.

Can't say what it does on the 5.5" rim and 180 tyre.
John M

austinpowers
Posts: 9
Joined: Tue Jun 23, 2015 11:22 pm

Postby austinpowers » Wed Apr 27, 2016 12:39 pm

McBoxer wrote:Interesting. I'm pretty sure the rim width measurement should be taken between the inner seating faces - ie, where the bead sits inside the wheel - so I would expect the outside of the wheel to measure wider. How much wider will depend on the design / material of the wheel of course.

Does this picture match the measurement you took?

Image


Measured up externally making allowances for where the bead sits inside the rim. If anything, I was on the conservative side...

In reply to SP, this means it is effectively a 5.5 rim so there should be no distortion with a 180 in situ. Also worth remembering not all tyre manufacturers 180 sections (for example) are the same. A Metzeler 180 may not be the same as a Dunlop for example. All I'm saying is, it may be worth people who want a 180 section on their bike to measure their 5 inch hoop first....

Great Britain
adam
Posts: 83
Joined: Wed Nov 15, 2017 6:40 pm

Re:

Postby adam » Wed Mar 07, 2018 10:27 pm

SP250 wrote:The 5" 1100S rim will accept a 180 section tyre but it pulls the beads inwards and therefore the profile is out of shape.
It reduces the width of the contact patch and makes the shoulders curve inwards also reducing the patch when leant over.

I have run both 180 and the correct 170 section tyres on the 5" rim and the difference was quite marked.
Bike was much nicer on the 170 and less "nervous" at the rear but also steering more positively. Tyres are cheaper too.

Can't say what it does on the 5.5" rim and 180 tyre.


A lot of people make this mistake on Buells too. The handling on a 170 section tyre is much more precise when fitted to the rim.


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