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Author Topic: Rear tire size ????  (Read 2469 times)

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drag-on

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Rear tire size ????
« on: December 11, 2009, 07:12:07 AM »
How are you people installing the larger tire on rear. Using a different swing arm ? on my 1970 750 it looks like I don't have room on sides, it would rub swingarm. ??? ???
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Offline Industrial Cafe

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Re: Rear tire size ????
« Reply #1 on: December 11, 2009, 07:36:43 AM »
you can get up to a 130/80/18 tire in the stock swingarm (avon road rider)
you just have to space out your brake stay arm on the drum to get it away from the tire.




or a 130/90/16.
« Last Edit: December 11, 2009, 07:42:36 AM by Industrial Cafe »
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Offline Really?

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Re: Rear tire size ????
« Reply #2 on: December 11, 2009, 07:40:48 AM »
The later swingarms are a bit wider too, like on the 78k (I think).  With those some go 140 and 150.
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drag-on

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Re: Rear tire size ????
« Reply #3 on: December 11, 2009, 07:52:27 AM »
Great.... That was fast, ;D Thank you.
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Offline Inigo Montoya

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Re: Rear tire size ????
« Reply #4 on: December 11, 2009, 08:01:00 AM »
The 77/78 swingarm allows a wider tire. the 77/78 rim is also wider to accommodate a wider tire too.
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drag-on

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Re: Rear tire size ????
« Reply #5 on: December 11, 2009, 08:22:16 AM »
I have two swingarms, but no idea what year they are. One has bolts on top that tighten down on chain adjuster bolts it looks like, and the other arm does not have top bolts.
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drag-on

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Re: Rear tire size ????
« Reply #6 on: December 11, 2009, 08:36:38 AM »
My rear tire says.... Cheng Shin  5.10-16   LOL, what the hell is that??   :D
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Offline Industrial Cafe

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Re: Rear tire size ????
« Reply #7 on: December 11, 2009, 08:39:34 AM »
5.10 is a 130/90 tire.

look at the swingarm pics on this page, it helped me on my swap.
http://forums.sohc4.net/index.php?topic=34880.0
« Last Edit: December 11, 2009, 08:43:32 AM by Industrial Cafe »
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everything I say is pure speculation and
I have no idea what I'm talking about  ._.

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Offline MCRider

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Re: Rear tire size ????
« Reply #8 on: December 11, 2009, 08:49:02 AM »
Quote from: drag-on on December 11, 2009, 07:12:07 AM
How are you people installing the larger tire on rear. Using a different swing arm ? on my 1970 750 it looks like I don't have room on sides, it would rub swingarm. ??? ???
The 130 is good info. I have a 140/70-17 on mine 1970 swingarm. But the 17" proably pulled the tire back far enough from the front of the swingarm to fit. The 130 as an 18 is probably max.

It will likely also hit your chainguard, if you want to run it.
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drag-on

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Re: Rear tire size ????
« Reply #9 on: December 11, 2009, 08:55:00 AM »
Great info, and the extended swingarm..... I saved the page. Very nice.

           Thanks guys
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Offline BobbyR

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Re: Rear tire size ????
« Reply #10 on: December 11, 2009, 12:42:33 PM »
I have a 78K so i had a lot of clearence and i admit it looks cool. On my newest tire I went down a size.

When you put a much wider tire on a stock rim the tire wears square. I used Battalexes and i liked them a lot. Like a sport bike tire you can get grip very far up the sidewall. That is the good part. As they square off, there is no longer a smooth transition from the center of the tire to the sidewall on a turn. This does not happen overnight, but it does happen and you can feel it. I am finding the bike more responsive with the current tire.
There was another thread from I think Hondaman concering adverse handling that occurs when the front tire is much wider than the rear.
Don't get me wrong I am up from the stock Bicycle looking tires, I just came down a notch from being maxed out.     
« Last Edit: December 11, 2009, 12:46:44 PM by BobbyR »
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Offline Industrial Cafe

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Re: Rear tire size ????
« Reply #11 on: December 11, 2009, 12:53:07 PM »
I used a 16x4.25 rim and a 130/90/16 tire, in case I wanted to go wider.
but now I miss the look the 18 inch wheel brought to the bike.

I'm thinking of going to an 18x3.5 and 130/70 tire.
I'm also running an '80 750K swing arm which is wider and longer by almost 3 inches.

just some ideas you might want to consider.
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everything I say is pure speculation and
I have no idea what I'm talking about  ._.

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Offline Yoshi823

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Re: Rear tire size ????
« Reply #12 on: December 11, 2009, 12:57:01 PM »
I had a 4.25"x18" cast wheel on the back of my 750F2 & the only thing I had to modify was the chain guard and the rear brake torque arm.See piccies...

This one shows the machined down rear disc with a Honda MB50 front caliper and made at work caliper bracket and torque arm.

This later one shows the 150/70x18 Metzeler ME1 in place on the 4.25 rim.
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Offline rynanza

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Re: Rear tire size ????
« Reply #13 on: December 11, 2009, 12:58:59 PM »
Quote from: BobbyR on December 11, 2009, 12:42:33 PM
I am finding the bike more responsive with the current tire.

I have a 78K.  What is the current brand and size tire you are using?
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Offline Inigo Montoya

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Re: Rear tire size ????
« Reply #14 on: December 11, 2009, 05:29:20 PM »
Well I use a spitfire 130/90-17 and it fits very well and looks good too.
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