What size of tires on cb750k dohc

[Haxxel]

Hi, I'm currently looking for tires to my cb750 dohc build. I want some old school style tires with a lot of rubber.
Like this beauty:


What i have find is that the preferred tires to achieve this look is:
Firestone deluxe champion
Firestone Military
Shinko E270
Coker diamond

Any more suggestions?

However, the big question is tire sizes:
Original the bike has 4.00-18 rear and 3.25/19 front.
But on many builds I see that people use up to 4.50/18 rear and 4.00/19 front. How does that work? So its possible to put on larger size tires and achieve a more bulbous look?

// Axel

 

[Bandoms]

I'm looking for this kind of tire style as well. Would you let me know if you find some?

 

[amc49]

It works but can make the front look bigger than rear if that big a front used, like dirt bike. Depends on the actual tire profile.

Earlier than '81 forks are .300 narrower between legs and that big on front will be crunching space. '81 and later forks are wider and no problem. The earlier wheels that fit the early forks are narrower too. 2.15 vs. 2.50 or so depending on model. The 2.50 obviously better with wider tire.

 

[Bandoms]

I'm looking at 16x3 wheels for the front and back of the '79 cb750. The tires I'm thinking of are 5.00-16. Would they fit?

 

[amc49]

If the pre'81 front fork I bet no. The actual fork hole to fork hole distance at the triple for the tubes is only 5 3/4" and the stanchions are thicker than tubes, as well you have made tire shorter meaning it will now be in line with the fender lugs instead of above them cramping you even more. With only 3/8" on each side for clearance gonna probably have issues there.

 

[Bandoms]

Do the 81 forks fit on the DOHCs? Also, is this just the front or is it on the back as well?

 

[amc49]

I know 130 fits on back and maybe 140.

Yes, the '81 DOHCs and up had the wider forks. The triple clamps and top bridge must change.

 

[Bandoms]

Are there wider forks that fit on the cb750 that are not Honda? I'm having some trouble finding '81 or newer forks.

 

[Damon]

So I could go for a 4.50-18 on the back wheel and a 4.00-19 on the front of my 1981 cb750f?