Front Fork Cir-Clips

[Mr_Sheene]

Please work on the basis that you're dealing with an idiot and this will go better for all concerned. I have a March 1970 CB750 and have recently stripped the front forks, which had been assembled by an ape with a hammer. As a result, I need all the usual, including new oil seal cir-clips. The old ones, despite being recently rebuilt (sic) were paper thin with rust. I was lucky to get them out. I can’t find any on the DSS web-site, so I checked Yamiya. Problem: They show Honda originals at 50mm (also at 100 Yen each, which must be typo) and Yamiya aftermarket at 47mm and 2000 Yen a pair. The price isn’t really relevant and if possible I prefer OE. I want what is best and correct for the bike but Yamiya don’t usually screw up, so what’s best and why the difference?

[Trigger]

Because there are two different type of forks. I have trade packs of them, if you give me the size you want I will pop a couple in the post 

[AshimotoK0]

Had the same problem ..ended up surface grinding some off another model that were 47mm (but thicker)  (may have been CX500). Yamiya prices are not a misprint I don't think. Like I have said before on here K0= £££ Moneypit Buyer beware 

[Mr_Sheene]

Graham, thanks for the information and the offer, I'll be in touch when I've measured them. Ash, thanks for the advice but timing is everything.

[Trigger]

Ash is correct as I looked for some 47mm ones for him. They are thinner than a std circlip and it is much cheaper to buy some std ones and grind down.

[Mr_Sheene]

It's always dangerous to give an old fool too much information. Now I'm confused, especially as I've had time to think. Were Honda running two fork systems in parallel or is this diversity due to their famous continuous development? My bike is March 1970 and starts 1029***, so if there was a change in production, do we know when it took place? Giving the old fool time to think resulted in me wondering if there is also two sizes of fork seal? I've only seen one on DSS and Yamiya but there again, I was only looking for one. I'll measure the old clips tomorrow and may even go beyond my pay-scale and try to publish them. Thanks for the help and advice, I own a bench grinder, so it could get really dangerous!

[AshimotoK0]

It's always dangerous to give an old fool too much information. Now I'm confused, especially as I've had time to think. Were Honda running two fork systems in parallel or is this diversity due to their famous continuous development? My bike is March 1970 and starts 1029***, so if there was a change in production, do we know when it took place? Giving the old fool time to think resulted in me wondering if there is also two sizes of fork seal? I've only seen one on DSS and Yamiya but there again, I was only looking for one. I'll measure the old clips tomorrow and may even go beyond my pay-scale and try to publish them. Thanks for the help and advice, I own a bench grinder, so it could get really dangerous!

I used a really posh surface grinder at work to reduce the thickness ..I personally wouldn't recommend doing it with an angle grinder or bench grinder. It was in desperation really that I did that .. I think all K0's had that smaller clip..  they also had a back-up ring up to 1039120  which is bl**dy hard to find but later fork seals eliminate it's use, as they are thicker.

The numbers are here (from Parts Book in my 750 mega dropbox files    )

The 47 mm circlips were CB450K1 parts (292)  then later CB450K3/K4 parts (319).

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[AshimotoK0]

Here (292 part)  ..but postage a bit steep but maybe he has other items you need.

 https://www.ebay.co.uk/itm/Honda-CL-450-Clip-Sicherungsring-Seegering-47mm-Gabel-Original-NOS/361864727266?epid=1614113344&hash=item5440d18ae2:g:vB8AAOxyaTxRSEOD

or David Silver for 319 part

https://www.davidsilverspares.co.uk/parts/by-part-number/partnumber_90601319000/

[Mr_Sheene]

Thanks a lot, the information is very useful. You're a better detective than me, I couldn't find the cir-clips on the DSS site. One little downside, what's the bit about thicker seals? Is that K2 onward after they changed the stanchions? DSS offers fork seals but with their history you have to know what you're asking for. I do need other stuff from Yamiya, so I may get them from there.

[AshimotoK0]

I just fitted the ones Yamiya sell for the K0  and didn't use the back up ring.

There's a 13mm thickness seal used on later bikes and a Service Bulletin on it. seem to think I used an 11 mm though (Trigger?) and not so sure early sandcast used a 9mm thick seal plus back up ring.

BTW you should download this Service Bulletin collection which  I did in one  combined .pdf document if you are working on a 750. (most of originals came from BryanJ.)

https://www.dropbox.com/s/xkkwyl5lteti976/CB750%20Service%20Bulletins.pdf?dl=0

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[Mr_Sheene]

Thanks for that, this fork strip is getting better and better. On my old CB550 it was such a simple matter but if I do this correctly, it won't need doing again before they stop making petrol. I have just been out to the garage and taken a couple of pictures of the cir-clips. They measure up at 50mm with a thickness of 0.0496 of an inch (Sorry but I still think in Imperial) which equates to 0.125984 mm. (Odd number). Thanks for your help, it will assist me in getting this right and thanks for the link. I hope the pictures are displayed. this is bit like giving a baby a machine gun!