Honda-SOHC

SOHC.co.uk Forums => CB500/550 => Topic started by: McCabe-Thiele (Ted) on February 16, 2023, 06:10:31 PM

Title: Tightening sequence for bar clamps ?
Post by: McCabe-Thiele (Ted) on February 16, 2023, 06:10:31 PM
What is the correct tightening sequence for the handle bar clamps please - looked in my manual not there?

Is it front bolts first then the rear ones?
Title: Re: Tightening sequence for bar clamps ?
Post by: Sesman on February 16, 2023, 06:25:08 PM
That’s a good question, Ted. I just tightened mine as equally as I could trying to maintain an equal gap between the upper and lower clamps.
Title: Re: Tightening sequence for bar clamps ?
Post by: Oddjob on February 16, 2023, 07:00:41 PM
Just do them equally Ted, only the front fork clamps need the front closed up.
Title: Re: Tightening sequence for bar clamps ?
Post by: Orcade-Ian on February 25, 2023, 03:23:14 PM
Now there's a funny thing!

Just decided to tidy up my bar clamps - just one at a time to save other hassles.  There is clearly a dot at the front and that end is definitely thicker - like the front wheel clamps.  Maybe it's just a Yank spec difference - dunno!

Here's a pic of one of mine - I'm going to treat these just like the front wheel - tighten the front one fully then use the rear as a pinch bolt.

[attach=1]

[attach=2]

Make up your own minds!

Ian
Title: Re: Tightening sequence for bar clamps ?
Post by: Nurse Julie on February 25, 2023, 03:26:21 PM
Makes sense Ian. I always remember front wheel clamps, handlebar switch gear and handlebar clamps always do up the front first and then the back second so any gap is facing backwards.
Title: Re: Tightening sequence for bar clamps ?
Post by: ST1100 on February 25, 2023, 04:00:10 PM
There is clearly a dot at the front and that end is definitely thicker - like the front wheel clamps.
I was about to mention that there supposed to be punch marks, indicating the [forward] position... typical Honda.
Same for bar, clutch/brake armatures and switches (as well as brake & sift lever) having the default ergos marked...
Title: Re: Tightening sequence for bar clamps ?
Post by: Lobo on February 25, 2023, 09:23:07 PM
Appreciate CB750 forks, but guessing the logic carries over…
Title: Re: Tightening sequence for bar clamps ?
Post by: Sesman on February 25, 2023, 10:37:27 PM
My original 77F2 clamps don’t have punch marks…just saying.
Title: Re: Tightening sequence for bar clamps ?
Post by: Sesman on February 25, 2023, 10:40:12 PM
Having written that, if the clamps are stepped then the same logic applicable to the fork clamps must apply.
Title: Re: Tightening sequence for bar clamps ?
Post by: McCabe-Thiele (Ted) on February 26, 2023, 06:58:07 AM
I had this vision of equal clamping on the handlebars to allow air flow thus preventing water to accumulate & cause rusting. ;D ;D ;D

Theory does not pass the same test for fork clamps where there is likely to be a much greater threat from water. :-\ :-\ :-\
Title: Re: Tightening sequence for bar clamps ?
Post by: K2-K6 on February 26, 2023, 08:05:18 AM
It's common engineering practice to design one side to touch, giving datum surface to clamp geometry and make the hole essentially round to match the spindle once that dimensionis established with first fixture (bars are going to be more varied in tolerancing than wheel component) then the second bolt only has to gently apply friction to stop it moving. Because it touches all the way round, if designed correctly, the torque to achieve clamping is relatively small.

It's very similar to the fork stanchion bore/clamp but with the convenience of being able to split it for assembly.

Both tightened to touching is a different joint, the crank mains being one, that doesn't clamp but tries to produce an accurate bore even though it had to be split for access.
Title: Re: Tightening sequence for bar clamps ?
Post by: Sesman on February 26, 2023, 08:51:50 AM
Like I said…if stepped….
Title: Re: Tightening sequence for bar clamps ?
Post by: Orcade-Ian on February 26, 2023, 03:34:53 PM
My own 400/4 also has stepped (as Sesman calls them) clamps - don't know about any dots because the washers are hiding that area.  My 350/4 has the row of idiot lights like 500 and that unit has no step so would be tightened evenly front and back.  Not sure if 550/400 for other markets are different arrangement and if life is only 1 day long, News at 10 has just finished, so can't be arsed checking!

(IDHTTL)



Ian
Title: Re: Tightening sequence for bar clamps ?
Post by: Sesman on February 26, 2023, 06:31:24 PM
Hey, Ted. Have a look in the Aladdin’s cave at ‘CB550 F1 set up’ manual and you will have your answer. Had a closer look at my clamps and there is indeed a punch mark on each clamp facing forward.
Title: Re: Tightening sequence for bar clamps ?
Post by: McCabe-Thiele (Ted) on February 26, 2023, 07:27:45 PM
Ill take a peek.
Title: Re: Tightening sequence for bar clamps ?
Post by: Sesman on February 26, 2023, 07:58:36 PM
Aye…page no6.
Title: Re: Tightening sequence for bar clamps ?
Post by: McCabe-Thiele (Ted) on February 26, 2023, 09:41:15 PM
Even though the 500 has the pilot light holder built into the bridge that seems pretty definitive Phil.
Title: Re: Tightening sequence for bar clamps ?
Post by: Oddjob on February 26, 2023, 10:46:23 PM
The 500 handlebar clamp isn’t stepped though Ted, not checked it but it seemed to sit on a flat surface flat
Title: Re: Tightening sequence for bar clamps ?
Post by: McCabe-Thiele (Ted) on February 26, 2023, 10:58:24 PM
The 500 handlebar clamp isn’t stepped though Ted, not checked it but it seemed to sit on a flat surface flat
Not sure what you mean by stepped - does that mean the front quarter is bigger than the rear quarter so as to speak?
Title: Re: Tightening sequence for bar clamps ?
Post by: Sesman on February 27, 2023, 06:42:59 AM
Yes, like the front fork axle clamp, Ted. Your clamps will be what they are, but the guidance is very definitive. The punch mark or higher step is to the front and the tightening sequence is front first, rear second. Seems fairly straightforward I’d say.