Honda-SOHC

SOHC.co.uk Forums => CB500/550 => Topic started by: MrBaklava on May 24, 2023, 03:13:37 PM

Title: Tyre sizes
Post by: MrBaklava on May 24, 2023, 03:13:37 PM
What are the largest tyres I can fit on the CB550 whilst retaining the original front and rear mudguards.

And, does anyone have any photos or 500/550s with chunky tyres?

Thanks in advance.
Title: Re: Tyre sizes
Post by: Oddjob on May 24, 2023, 04:21:54 PM
I've had 4.10 on the front and 4.25/85 on the rear with no problems. Think that's 100 and 110 in metric. I've heard of 4.50 on the rear but not seen it personally. I'd say 4.10 is about it for the front.

(https://i.postimg.cc/nznwKZyV/scan0005-1.jpg) (https://postimages.org/)

Not the best pic but that's wearing the above tyres.
Title: Re: Tyre sizes
Post by: flatfour on May 24, 2023, 04:41:47 PM
I always used to fit a 4.10 19 inch TT100 front and 4.10 18 inch TT100 rear to my 500's.

This combination was recommended to me when I bought my first 500 by the supplying Honda dealer in 1972 and, although I've owned a few of them since, there has never been a reason to change it.
Title: Re: Tyre sizes
Post by: Oddjob on May 24, 2023, 04:53:08 PM
I always used to fit a 4.10 19 inch TT100 front and 4.10 18 inch TT100 rear to my 500's.

This combination was recommended to me when I bought my first 500 by the supplying Honda dealer in 1972 and, although I've owned a few of them since, there has never been a reason to change it.

Which is odd because the rim width didn't really lend itself to fitting tyres that wide, 3.60 was about the limit of the 1.85 rims fitted to the 500. Anymore width that that and you got rim creep and tyre wall flex in the corners due to the rim not being wide enough to support the tyre width. It's why I fitted Lester wheels with the wider 2.15 rims. Before fitting the Lesters I thought 4.10 front and rear were about the best it could support but a Honda dealer shouldn't be recommending that size as they knew it wasn’t  recommended.
Title: Re: Tyre sizes
Post by: Bryanj on May 24, 2023, 05:03:29 PM
3.50x19 front and 400x 18 rear in real sizes is the biggest but that rear for a 550 rim not a 500 rim.
Title: Re: Tyre sizes
Post by: flatfour on May 25, 2023, 05:06:51 PM
Although I am sure that you are right, I can only say that over three 500/4's and probably around 60,000 miles or so between them, I didn't suffer any problems.

With the first two, bought in the very early 70's, the tyres were changed by the dealers before collection of the bike. At my request they fitted TT100's in the sizes that they thought best suited. Interestingly enough, the two (Honda) dealers involved were almost 100 miles apart and, to the best of my knowledge had no links with each other. The change of dealer for the second bike was only due to extreme shortage of the supply of 500's in those days, so when I saw one in the window whilst out for a Sunday run, I went back and ordered it on the Monday!

The lead mechanic for the dealer that I first bought from had used to attend meetings at our local Club and he also ran a 500/4 fitted with the same tyre size and type. His employer raced Honda's in the I.O.M TT at that time.
Title: Re: Tyre sizes
Post by: Oddjob on May 25, 2023, 05:18:49 PM
It was common in those early days to run 4.10 tyres, although 3.60 and 4.10 were the most common combination, the problems only really became apparent when people started to race them and found the limitations of the rim size, the 750 didn’t suffer with it as much as it got wider rims so the 500 was the test bed so to speak.

As I said I ran 4.10 tyres on 1.85 rims and found them ok for normal riding, it was only when pushing the envelope that they started to show just how unsuited to the rim size they really were. The Lesters with the wider rims and more rigid structure made the bike handle like a dream, not that the 500 wasn’t good before, it just became even better.
Title: Re: Tyre sizes
Post by: McCabe-Thiele (Ted) on May 26, 2023, 12:18:37 PM
My 500 had 1.85 x 19" rims fitted with 3.25 x 19 tyre.
Rear rim had been upgraded to 2.15 x 18" rims fitted with 4.0 x 18" tyre.

Rear wheel looked beefy.




.(https://live.staticflickr.com/65535/52394612731_2e9b0ebb68_o.jpg) (https://flic.kr/p/2nPW5XV)engine out (https://flic.kr/p/2nPW5XV) by Macabe Thiele (https://www.flickr.com/photos/187487200@N03/), on Flickr
SimplePortal 2.3.5 © 2008-2012, SimplePortal