Honda-SOHC

SOHC.co.uk Forums => CB750 => Topic started by: DaveB on April 04, 2017, 10:09:03 AM

Title: Gauge Repair
Post by: DaveB on April 04, 2017, 10:09:03 AM
I knew when I got my CB750 project that I would need to repair the gauges, especially the rev counter as it had quite serious dents in the outer housing. Therefore I immediately ordered new faces, black housings, glass, rubbers and rings (to reseal them) from CB750Faces.com who I believe is highly respected in these parts. I watched all the videos I could find on gauge repair and so when the parts arrived I set about the rev counter first.

The first problem I encountered was that I absolutely could not remove the needle using two teaspoons, a fork or anything else. In the end the only thing that worked, having decided the old face was rubbish anyway, was prising it off with a screw driver. However, in this entire process of trying to remove the needle, and to prove I am fully capable of being a complete idiot, I managed to wind the needle past the stop and therefore would up the coil spring this rendering the gauge completely useless.

This is all just a bit of background really as it's mildly amusing and gives me a chance to own up to my stupidity, from which I will learn.

I rebuilt the gauge anyway because I wanted to see how difficult it could be and this is where my main problem lies. No matter what technique I use, what tools, how patient I am, how much drain pipe I cut off or how many metal clamp rings I use etc. I simply cannot get the new rings bent back onto the gauges in any sort of fashion worth anything. I ended up using the old ring, but even though the 'damaged' side presses against the rubber of the housing, it was still obvious it had been reassembled by a ham fisted metal nibbling no clue idiot.

I've now managed to obtain a new (second hand) set of gauges so at least I have a working rev counter again but I'm left with a fairly expensive set of parts with which to repair both the rev counter and speedo which I can't use because I know I won't be capable of re sealing the ring in any fashion worth a squat...

So my question (finally) is this... Is there anyone in Kent or the SE that would be able to fit new rings to my gauges if I went ahead and did all the other work or am I just going to have to swallow the expense of the spare parts I bought and get them fully refurbished elsewhere?

Many thanks for listening :)
Title: Re: Gauge Repair
Post by: RGP750 on April 04, 2017, 10:28:52 AM
Would you like me to take a look?
Rich
Title: Re: Gauge Repair
Post by: Johnwebley on April 04, 2017, 10:47:08 AM
Would you like me to take a look?
Rich

  you could also try   KENT400,,   he rebuilt a couple of  gauges for me,they look great

BTW,he is a member here
Title: Re: Gauge Repair
Post by: DaveB on April 04, 2017, 01:49:36 PM
Would you like me to take a look?
Rich

Are you any good at putting the new rings on? Honestly sorry, I don't mean to be offensive, but I don't really know who's who here yet and what expertise people have. If you are good at this then yes, I'd love you to take a look.

I clearly have no expertise at all in this task although it seems I'm OK with the rest :)

I actually can't for the life of me see how anyone could ever make a neat job of it unless they're pressed on like Honda surely did with the originals?

Title: Re: Gauge Repair
Post by: Trigger on April 04, 2017, 03:28:30 PM
I would pop the clocks in a bag and go and visit Rich just south of Ashford, you will be amazed what he does for a living.
Title: Re: Gauge Repair
Post by: Nurse Julie on April 04, 2017, 06:22:11 PM
 ;D ;D ;D ;D ;D .......he wishes.
Title: Re: Gauge Repair
Post by: RGP750 on April 04, 2017, 06:54:04 PM
Ha! Ha! Ha! Dreaming ;D ;D ;D ;D
Title: Re: Gauge Repair
Post by: JamesH on April 04, 2017, 07:06:11 PM
What he does is very very sexy indeed...and sometimes involves latex apparently ...
Title: Re: Gauge Repair
Post by: RGP750 on April 04, 2017, 07:09:53 PM
Remind me to tell you about one of my jobs i did for someone in Brighton a few years ago James.
Latex well Silicone actually ;)
Title: Re: Gauge Repair
Post by: DaveB on April 04, 2017, 07:36:26 PM
Very scary. Sounds like I should use a plain brown paper bag? :)
Title: Re: Gauge Repair
Post by: RGP750 on April 04, 2017, 07:37:30 PM
Well we did 8)
Title: Re: Gauge Repair
Post by: BigAl (Alan) on April 04, 2017, 07:39:10 PM
Job for a specialist, especially the damper fluid...I'm no expert, but I'm sure someone will point you in the right direction.

I re-faced a couple of clocks a few years ago,  made a timber jig (as image) which helped with the removal & re-fit of the locking ring.

Alan
Title: Re: Gauge Repair
Post by: kent400 on April 05, 2017, 10:48:05 AM
Fair to say the bands on the larger gauges are not too easy to fold back, the gauge needs to be clamped to compress the rubber seals to get the band edge above the base flange and to ensure the body isn't loose on the base. A drill press with a piece of 6mm round stock in the chuck is utilized, the gauge is simply revolved and pressed back to the base flange. A very reasonable appearance on the underside can be achieved but this can't be seen when fitted. The wood block is made of several pieces of MAF glued together, this protects the top edge of the band and the paint finish on the body.

It's a bit of a task forming the wood block but it might be possible to use a piece of plastic drain pipe that the gauge will drop into up to the band if the pipe is marginally too big a cut along the length and closed up with a couple of hose clips might work. I've not tried that and only thought about the possibility have made about 4 blocks to suite various size gauges over the years.
Title: Re: Gauge Repair
Post by: AshimotoK0 on April 05, 2017, 10:53:03 AM
Fair to say the bands on the larger gauges are not too easy to fold back, the gauge needs to be clamped to compress the rubber seals to get the band edge above the base flange and to ensure the body isn't loose on the base. A drill press with a piece of 6mm round stock in the chuck is utilized, the gauge is simply revolved and pressed back to the base flange. A very reasonable appearance on the underside can be achieved but this can't be seen when fitted. The wood block is made of several pieces of MAF glued together, this protects the top edge of the band and the paint finish on the body.

It's a bit of a task forming the wood block but it might be possible to use a piece of plastic drain pipe that the gauge will drop into up to the band if the pipe is marginally too big a cut along the length and closed up with a couple of hose clips might work. I've not tried that and only thought about the possibility have made about 4 blocks to suite various size gauges over the years.

I am making up something similar for the CB72/77/Bomber/JDM CB250K0, that have combined speedo/tacho in an oval enclosure . Once I get the outline on CAD I am going to have a piece of plastic milled out to suite. What do you do on those old 1960's 'clocks' Peter? Any hints & tips?
Title: Re: Gauge Repair
Post by: DaveB on April 05, 2017, 11:11:08 AM
Fair to say the bands on the larger gauges are not too easy to fold back, the gauge needs to be clamped to compress the rubber seals to get the band edge above the base flange and to ensure the body isn't loose on the base. A drill press with a piece of 6mm round stock in the chuck is utilized, the gauge is simply revolved and pressed back to the base flange. A very reasonable appearance on the underside can be achieved but this can't be seen when fitted. The wood block is made of several pieces of MAF glued together, this protects the top edge of the band and the paint finish on the body.

It's a bit of a task forming the wood block but it might be possible to use a piece of plastic drain pipe that the gauge will drop into up to the band if the pipe is marginally too big a cut along the length and closed up with a couple of hose clips might work. I've not tried that and only thought about the possibility have made about 4 blocks to suite various size gauges over the years.

Very many thanks for the explanation of your method. I can see how you could achieve a reasonable appearance and reseal the gauges properly using this method. Does it also work as well with new rings? I'm curious because I reverted to using the old ring simply because the edge was already slightly bent over (and it it had been weakened with the removal). The new rings have no such pre bend as such and so the edge sits bolt upright in relation to the gauge and I couldn't even get one to start bending. This could well have been through fear of not wanting to break anything of course. Anyway, could you please let me know if your same method works with new rings or if you have to use a different technique.

Many thanks,
Title: Re: Gauge Repair
Post by: kent400 on April 05, 2017, 01:09:15 PM
Ash, I just use a piece of MDF with an oval hole in it and the gauge is just a tight fit to prevent the bezel spreading outwards. There's another piece of MDF stuck underneath to bring it to the correct height. Also on assembly using the drill press method the bezel won't distort.

The second question on the subject of the replica CB750F bands, I've never fitted one as I've always re-used the original and it's entirely possible if it's removed correctly. I did see a comment on here regarding the replica bands and I seemed to remember the forum member found they were too big. If that's the case they would be difficult to fit as there is so little material to fold over the base flange. 
Title: Re: Gauge Repair
Post by: philward on April 06, 2017, 12:31:32 PM
This is how I did it
http://www.sohc.co.uk/index.php/topic,8542.msg57418.html#msg57418