Wider Tire Widths

troybilt said:
I'd like to throw a question into the mix if I could. Advice stated earlier in this thread was that if we go up one tire size we will probably kill ourselves. I think that is about how it was put before the post was removed. Anyhow, I'm wondering how does one guarantee they are replacing the same tire size since most manufactures measure that same size tire differently?
My disclaimer is the same as stated before; I really don't claim to know wtf I'm talking about. So take it for what its worth.

Going up one size from STOCK usually wont cause problems, (i.e. from 3.00" to 3.25")
As long as you know stock size or are willing to find out and are aware it will make tyre taller than stock and probably have less rubber in contact with road when upright.
Its the people who want to put 4.00 tyre on WM0,(1.4") WM1,(1.60") WM2 (1.85") rims that are going to have issues
WM3 rim is 2.15" and about smallest size to safely fit 4.00 tyre.
Heres some links to go with the ones already posted
http://www.cb450stuff.com/tires/
http://www.usmotorcycletires.com/tire_size_conversion_chart.php

PJ
 
Issues are relevant. Issues at 25mph could be different from issues at sustained highway speeds.

Although I know of people doing both and not having any problems.

I wouldn't suggest that someone run a 3.50 on a 1.6" rim, but that doesn't mean I won't.
 
I had pretty much forgotten about this particular bike (Honda CBX550)
http://dotheton.com/index.php?topic=11758.msg105246#msg105246

If you fit oversize tyre to front, it becomes virtually unridable around 35~40 mph.
'we' had one brought in for 'handling' problem, it was real scary, never before had a bike go into a tank slapper at 20mph.
Messing with tyre pressures didnt do any good, or adjusting suspension setting/air pressure
Fitting correct size tyre 'cured' all the problems

PJ
 
I have a 76 CB750A with a 19 front -- could I run a 4.00 19 tire on that thing safely? I went out and bought one without really 'researching' it..
 
How wide is your rim? It will be stamped on it. Take that and then look at the manufacturers recomended rim widths for your brand and model as they all differ. If you rim falls in the range you should have 0 problems, if it is only slightly too small, I wouldn't worry, but if it is a large difference, and you are going to run freeway speeds a lot, I would get a different tire. What will happen as PJ put it, you will screw up the shape of the contact patch, and pinch the tire at the bead too much and it can over heat, or wear funny or blow out. Now cruising around town at 30-40 mph it is likely not to cause any issues but get the speed up and the length of time at speed and it could be evil bad. Just my .02. But you can get the info on the tire and make an educated decision. Recomended rim width might even be stamped on the tire itself.

Cheers,
 
Maritime Biker said:
How wide is your rim? It will be stamped on it. Take that and then look at the manufacturers recomended rim widths for your brand and model as they all differ. If you rim falls in the range you should have 0 problems, if it is only slightly too small, I wouldn't worry, but if it is a large difference, and you are going to run freeway speeds a lot, I would get a different tire. What will happen as PJ put it, you will screw up the shape of the contact patch, and pinch the tire at the bead too much and it can over heat, or wear funny or blow out. Now cruising around town at 30-40 mph it is likely not to cause any issues but get the speed up and the length of time at speed and it could be evil bad. Just my .02. But you can get the info on the tire and make an educated decision. Recomended rim width might even be stamped on the tire itself.

Cheers,

Good advice Maritime. Very well said and I couldn't agree more.
 
1.85. Drat! MB, thanks for the info. Always a very knowledgeable dude. I guess I'll pull a Wrenchmonkees and run the thing, but maybe I'll keep it off the freeway. ;_;
 
Here's a little bit of fun for you......

Give Coker a call and ask a tech what rim they recommend for the Firestone Champions.


skinny.....
 
Deli Sandwich said:
What tire widths are possible with the stock rims.
I want to run 400/18s front and rear, but I'm curious on what will actually fit.
How do you determine the rim width, when there are tires already mounted?

Im referring back to this thread, http://dotheton.com/index.php?topic=6211.0
because it's basically the same questions I have. Except I'll be running Avons or Cokers instead of the Firestones. SoCal freeways have grooved lanes, that make the Firestones a swerving nightmare.

p.s. Should this also be the Brat forum?

450/18 Firestone Deluxe champions, Front and Rear
 
Back
Top Bottom