Blog: up and down, but not side to side.

Got the YZ swinging arm back from Revs this morning fitted with new
pivot needle roller bearings. £25 labour - which I thought wasn't bad at
all given the struggle I would have had to get the ancient rusted ones
out, never mind persuade the new ones back in without damaging them. A
good 'it's a small world' chat with John, who it turns out was an SWM
dealer as well as a sidecar trials expert, and remembers me from when I
used to observe on the Vic Britain trial in the 70's. His tiny workshop
is like an Aladdin's cave with rows of fork legs and rear shocks being
serviced and the odd MX motor in pieces.

Assembled with the new style plastic thrust bearings I was pleased to
find that it slipped back on snugly and once the pivot bolt was torqued
up rotated smoothly with no side play. So I bolted the relay arm back in
to position and connected up the rear shock. Bollocks - still a bit of
lost up and down movement in the system somewhere. This was traced to
the bottom mounting bearing thing on the shock, which was utterly
shagged. Yippee - the clever folk at 'All Balls' had included a new one,
complete with seals and bushes in the kit. More magic with a 10mm coach
bolt soon had that swapped. This was made much easier by my bearing
driver kit, recently purchased off Ebay, which has a selection of
several stepped alloy discs of various OD. Much quicker than trying to
find just the right socket and I can see the larger ones together with
the QD bashing handle being useful for putting wheel bearings in.

The rear wheel slipped back in without drama, and I can now see that
even if I eventually go for a 17 inch rim I won't be able to go bigger
than a 150 tyre without fouling the swinging arm. Sprockets are on
order to give a range of gearing and it looks in danger of being ready
in time for Hartland.


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+-------------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+-------------------------------------------------------------------+

 

<snip>


<blog>

Recent progress on the CB72.. Got the carb rebuild kits but they're
still pissing fuel from the overflow, traced to both floats being
porous, so, 2 new floats on the way from the US.

While waiting for the floats I filled the forks with oil and adjusted
the head bearings, hopefully that's the front end sorted. Also cabled
and adjusted the front brake - turns out I have the front cable for the
high bar model, so it's too long. Arse.

Also finished the wiring, so all lights and the horn work.

Bit worried about the play on the gear lever, you can just select 1st
and second with the available travel. Mucho wear in the unobtainable
gear lever and the clevis pins/linkages. Have to see if it's really bad
when riding.

Apart from sorting the carbs it's pretty much finished.

</blog>

 

One of the plus points of working on SO competition machinery is the
lack of wiring to sort out. In fact I have stripped off the vestigial
lights that it did have when in road legal (well in France anyway)
enduro trim.

I would have thought you might be able to sort generic clevis pins etc.
The lever is a bit more of a problem. Is it worn on the pivot - so
possibly could be fitted with a one-off bush?


--
+-------------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Yamaha WR250Z/Supermoto "Old Gimmer's Hillclimber" |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+-------------------------------------------------------------------+

 

The lights weren't that hard once I'd found out what the headlight
switch was supposed to do. Simple on/off - hahahaha no.

Yep, been suggested I could get a slightly larger pin and drill the
linkages to suit. Bushes for the gear lever can also be molished, but
not cheap - so I'll wait and see how bad it is when riding.

I might hate riding the thing and Nige it at the first opportunity for
the next project. Or I might actually like the cursed thing.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Mike Buckley

Really? If only you knew someone who'd knock them up for a beer.

Oh wait! You do!

 

Yes, I may indeed be calling on WUN Engineering, seeing as Phil Denton
charges considerably more than a beer, and considerably more than a lot
of people are willing to pay.

Will have a closer look and see what needs to be done.

 

I *think* these can be re-bushed.

 

Mentioned it to one of the CB gurus (whilst buying the right length
brake cable) and he suggested buying the next size up clevis pin and
drilling the linkage to accept it, either that or bodging it by using
feeler gauges round the pin.

I've had a closer look and there's around an inch of free play at the
end of the lever. Most of the slop around the gearbox lever pivot is
side to side and the majority of the problem is definitely the clevis
pins and the linkages.

Buy a bigger pin and drill to match, or will it just make it worse?

 

Bad form etc

http://www.phildentonengineering.com/product.asp?pid=104

 

Are the linkages rose-jointed? You can buy new from motorsprot shoppes.

 

You fill it with weld and drill out a new standard hole. Easy.

 

If I had a welder and a pillar drill perhaps.

The CB forum has suggested buying some ball/socket joints to replace the
clevis pin arrangement. Cheap enough to give it a go (They're not rose
joints).

 

It'd look like a back garden bodge and on a fully restored bike that'd
be ridiculous.

 

I've found a company (Springfix) online that do the clevis joints in
stainless, so I'm ordering a couple of those. Not cheap tho', nearly a
tenner each, plus delivery, plus "small order surcharge".

 

Perhaps if you do it, maybe.

 

Yeah, one day I'll have a few lessons in getting something welded up
and re-machined.

I'd just make a new one if it was my bike but that's because I'd want
it right.

 

Pah, many's the time you've said you don't weld.
Anyway, there's nowt wrong with rebuilding and re-using the original
part - much more of a proper restoration, especially if the replacements
are unobtainable. They're not really in this case, but ykwim.

 

I don't weld. That doesn't mean I can't weld, it simply means I don't
do it or I'd get someone else to do it for me if I thought it was the
right way to go.

Repairing the original parts is fine but the problem is that they're
often made of shit materials and it's better to make new.

 

You're very close in that I can weld if I really need to but I don't
enjoy welding so usually get someone else to do it for me.

It's bit like owning a dog and barking yourself iyswim.

 

Adding's too tricky, eh? You stick to taking away.