Topic: Fork tube nut from 450 for a 500F

[jamesbekman]

Hi Everyone,

I have a CB500F and I bought new fork tubes from Forks by Frank. 

Since the fork tube top nut is not made anymore, I read that you can still buy a 450 nut and have it work.  I bought them and they are the same thread.  There just seems to be a little bit of a gap between the top flange of the nut and the fork tube.  Does anyone else have a similar experience?  Should I use a washer to make up for the difference?  The 500f nut and the 450 nut are different lengths.  Is there anything I should be concerned about?

[City Boy]

Hi.I am assuming the 450 bolt is the longer one and is reaching the bottom of the fork thread before the flange on the bolt contacts the top of the fork.Assuming also that the sealing o-ring on the bolt is fully inside the fork I think using a washer would be A ok. For a cleaner look though I would suggest grinding some off the bottom of the bolt.   Rock On

[City Boy]

Idealy,you would want your new bolts to be made the same length as the originals so that there is no change in fork spring preload if no change is desired.

[jamesbekman]

Thanks.  Ill take some pics when I can of the difference.  If anyone else has any experience with this please by all means chime in.

[Bankerdanny]

CB500F?

[jamesbekman]

1971 CB 500F K0

[Bankerdanny]

I assume you mean F=four.

In the SOHC4 world F typically designates a Super Sport model (except for the CB350) with the signature feature of a 4-1 exhaust (and a rear disk for the 750F).

The 500 only ever came as a K bike. The 550 and 750 came as both an F and a K. The 400 only as an F (Super Sport)

I'm not trying to be a jerk, it's just important that you describe your bike correctly when asking questions so that you get accurate answers.

[jamesbekman]

 Thanks Danny,

Yea F meant four to differentiate a four cylinder to a two cylinder as they have different forks.

I only thought they made super sport 550 models.  Thanks for the info and clarification. 

[Bankerdanny]

No problem. That's what this forum is all about.

Just to add to the fun, the the 350-four was called the CB350F, but unlike the F models for all other SOHC4's, the 350F has the 4-4 exhaust found on the 500/550/750 K bikes.

I suspect Honda did that for the same reason you did, to differentiate between the twin and the four since they were available at the same time.