Topic: CB750 experts opinion wanted, front fender and brake lever questions

[spitfire]

OK, all I had to do was fit the front fender, wheel and front brake, all parts in stock and an easy job, not so as I found. When I went to fit the front fender (used, bought from eBay) I noticed that the stays (UK bike so 2) had no rubber mounts where the stays bolt to the bottom of the fork legs, and on the speedo drive side of the main fender mount, the holes were smaller and would not accept the rubber mount. No problem the stays on my old rusted out fender were Ok so I fitted them. Then I fitted the front wheel and found that the hydraulic pipe bracket was catching on the tyre, a closer look revealed that the new fender mount had a rivetted bracket that stuck out at the back catching the tire. The original fender had a welded bracket, this was flush on the inside of the fender mount and did not catch the tire.
This was not a problem as I was replacing the old brake lines with braided hoses so did not need the pipe mount so I ground it off.
However I do want to eventually replace the front fender but do not know if later ones are the same design as my eBay one, or is the fender for another model, any ideas ? Seen this same problem in an earlier thread but with no conclusion.
The second question is about the front brake lever, when I bought my 750F in 1976 I noticed that there was about a 1/4" gap between the lever and the brake piston, so I cut a section of bolt of the appropriate diameter and popped it into the gap which took up the slack. I have just rebuild my MC and caliper and the same gap is there, I came across a brake lever with a pan head screw (spare MC from eBay) which looks like it cures this (see photo) is this a Honda mod or a better bodge than miine ? I a recent thread someone found a dime doing the same duty !

Cheers

Den

Original fender mount with flush bracket.


Ground off bracket


Brake lever




Completed job

[eldar]

did I see that right? On your tire, does it say 4.1 as part of the size? If so, that will probably be an issue. The tire does look awful fat under that fender. My 110/90 does not look that big.

[spitfire]

The tire is a 410.19 TT100 (replaces 350.19) which is the tire that I normally use, no problem with clearance on with the old fender, just with the new one. Well spotted though !

Cheers

Den

[333]

The fender you bought may not be what you thought, but let's be clear about one thing.  A 4.10 is not a replacement for a 3.50.  If the number to the right of the decimal is in .25 increments, then the width of the tire is just that.  Example: 3.50 is 3 1/2 inches wide, 3.25 is 3 1/4 inches wide.  Tires in these sizes have a standard profile(height) of 90%.  So the 3.50 X 19 is 3 1/2 inches wide and 3 .15 inches tall.  In the case of the 4.10, the .10 means 100% profile, so it's 4 inches wide and 4 inches tall.  In the case of a 4.85, it's an 85% profile.  In metric sized tires, the second number is this same method, a percentage of the first number, with 90 being "standard", as width.

The difference between 3.15 and 4 will throw your speedo way off.

[spitfire]

Wow, they say you should try to learn something new every day, well I've been educated, wonder how much faster (or slower) all my bikes have been, used the same brand and sized tyres on my KO, K2, K1 and the F1. It is actually printed on the tire that it replaces 350.19, but obviously I didn't know the implications until now.
410.19 on the front and 425.18 on the rear (TT100's)

Thanks

Den

[mcpuffett]

Hi Den, bikes looking good  , had a look at my bikes today and my f1 is the same as yours with a welded on pipe guide , my brake lever is ok on my f1 with hardly any play and about 1/4 of an inch play on my KO, i have also been running TT100's and the same sizes with no issues , i have just fitted a pair of Dunlop Gold Seal tyres to see how they wear as i was only getting about 3,000 out of a back tyre , cheers mick.

[spitfire]

Hi Mick,
          Tried that bodgy lever and was not impressed, the metal used for the brake piston and is very soft, the head of the screw left a distinct impression, so I have resorted to my old method of a steel disc between the lever and piston.
Rolled out the bike into the sunshine yesterday, the first time in a year and a half that its been mobile, spent today checking the oil pump strainer, it was clean as a whistle, but I had to swap sump pans anyway. The NOS exhaust header is loosely fitted, will finish that tomorrow. Just got to fit the new points plate, find and fit a battery, empty the 12 year old petrol from the tank, refill it with good stuff and maybe see if it will run.
What size tyres did you end up with, I seem to recall that I only got about 3K with the TT100's in the olden days, where's the F2 photos ?

Cheers

Den

[fuzzybutt]

 a 100/90/19 is what that bike needs on the front.