REALLY need some front end knowledge/help.

R100 · Post by **R100** » Sun Mar 08, 2015 3:46 pm

First some background.
The frame # is meaningless as this bike was thrown together from parts of 3 bikes.
I had wanted a CB77 for a long time, did not think it could be too bad, completely misjudged the seller, and bought it.
I have remedied numerous things. But this! What is wrong with people!

The forks have steel lowers. Type 1.
Removal of the front yokes/forks was very difficult. When I got the big nut off the top yoke the stem jolted off centre.
After inspection I am sure I have top/bottom yokes that don't match. CMSNL diagrams list 4 of each. It seems the offset (main stem hole to a line between centres of the fork holes) is different by about 5mm. Picture is of the two yokes slid together

While I head scratch (and curse), it would be great if some of you chaps could shed some light on this.

G-Man · Post by **G-Man** » Sun Mar 08, 2015 4:20 pm

R100

I think the offset changed between early and later forks. What is the diameter of the holes in the lower clamp? Very early ones were 38mm like my 1961 bike up to 63, I think.

The ones with the alloy lowers were 32mm and the later steel bottom ones I cannot remember off hand. If we can establish which forks you have we can then start looking for the top clamp for you. I have several here that I could compare for you.

I'm guessing that you have a top clamp from a set of alloy-bottom forks, but I've never looked in detail.

G

R100 · Post by **R100** » Sun Mar 08, 2015 4:32 pm

Diameter of the holes in the bottom yoke is 34mm and a bit (unbolted).
The tubes are 33mm where they slide, and 32mm above the taper.

Hoosier Tom · Post by **Hoosier Tom** » Sun Mar 08, 2015 6:27 pm

G's right. You have a top bridge for the alloy sliders, part number 53230-268-060. what you need is the one on the left in the following photo. (Note, I believe you have to be logged in to view photo.)
http://www.honda305.com/forums/download.php?id=5400
See how the bottom is recessed machined compared to the flat of the later one on the right like you have.

HT

R100 · Post by **R100** » Sun Mar 08, 2015 6:35 pm

Hoosier Tom wrote:G's right. You have a top bridge for the alloy sliders, part number 53230-268-060. what you need is the one on the left in the following photo. http://www.honda305.com/forums/download.php?id=5400
See how the bottom is recessed machined compared to the flat of the later one on the right like you have. HT

Understood. If I look for a yoke with that recess on the underside, will that be the correct one?

Hoosier Tom · Post by **Hoosier Tom** » Sun Mar 08, 2015 6:37 pm

Should be..

http://www.honda305.com/forums/download.php?id=5398
http://www.honda305.com/forums/download.php?id=5399

HT

R100 · Post by **R100** » Sun Mar 08, 2015 6:49 pm

Hoosier Tom wrote:Should be..

http://www.honda305.com/forums/download.php?id=5398
http://www.honda305.com/forums/download.php?id=5399

HT

OK. Thanks HT. The one on the left with the recessed holes.
That makes it clear and narrows down the shopping.

I will be nagging again tomorrow as my type 1 forks have some damage. Probably be shopping for those as well.