Tank Coating, part deux

My tank is being painted, thanx dad.
We had a big can of red, so that's what color the tank is going to be. Decided to remove the old emblem mountings as they were pretty mangled, probably will look better with a classic set of honda wing stickers and some silver stripes running along the length, just like the old RC tanks.

I'm liking the way this looks, might just put it back on my SS50Z moped, to make it look more like the way it used to, long ago:

Same tank by the way, one or two crashes earlier...

122cc motor cylinderhead

Done a little bit of work for my S90 in between all the other projects.
The plan is to build another engine, bored and stroked to 122cc by using ATC110 parts, cylinder, crankshaft and head. Only the ATC110 head has separate valve seats which are pretty thin, which means there is not enough material in them to install a bigger inlet valve.
A while ago I recieved a head from someone, probably C90, that had a full cast in combustion chamber, much easier to put a larger valve in there, but this head didn't fit the ATC110 cilinder.
I had to machine the space for the top of the cilinder, and also the studbolt hole where the oil comes up, as the ATC110 has a large rubber collar there and the C90 head didn't have a space for it.

ATC head on the left, C90 on the right.

the valve I plan on using compared to the original S90 inlet valve

when made to fit the head, this motor will breathe a little easier.

little changes

Some little changes have been made to my SS50, just a crappy pic in the dark, but it's wintertime, it gets dark soon and I didn't have my exhaust mounted in time to make pictures in the light.
Custom painted tank emblems, exhaust that came off my motorcycle, different seat, CB50 shocks and a slightly different taillight (short lens type)

BMW front forks

I've done a lot with the front forks of my BMW, stiffer springs, more preload, thicker oil, shortened original springs...
I pretty much had a good setup for a while, eccept for the occasional tankslapper at slow speeds.
Back in the day, they sold tubular fork braces, that I thought would make a great period specific addition to my bike, so I bought one off ebay, mounted it to my bike and as the weather was sort off nice, I had a testride.

I wasn't at the end of the street yet, or I had the worst tankslapper yet...
I had hoped this would be pretty much the answer to all problems, but it turned out to open up a whole new can of worms.
What to do now?
Another period upgrade for the front forks were alloy top yokes that clamp the forklegs instead of the original bolted connection. I've seen them on ebay, and they are not cheap. But what I've seen before, was that some people make their own by using a bottom yoke as a top, and as we had some bottom yokes laying around, I started adapting one.

In the picture you can see what will be the underside of the top yoke, I machined it down so my clip-ons could remain as high as possible for comfortable road use.
I also machined the center hole to fit the stemnut.
and then mounted it, as it was still sort of nice weather, I had a testride.
Yess, this made a dramatic inprovement in handling, not perfect yet, but were atleast getting close again. Now that the forks are much stiffer, I might just need thinner oil again.

Now I just need to finish the yoke, some more material needs to be machined off to be able to tighten the stemnut, I'm just not sure yet what to do.
Leave it as is, showing the raw casting with the numbers and logo, or machine the whole top flat and polish it to get one flat shiny surface....what do you think?

Tank Coating

My dad has been working on one of his Beemers, that will need its tank coated...this got me thinking about an old SS50zk1 tank I had laying around.
When coated it would be usable again, if something could be done about the mangled filler opening.
And so this project began:

the original opening has been cut out and replaced with an original Honda flip-up cap that was cut out of a CB-motorcycle gas tank.
I never really liked the looks of an SS50z tank, but this really makes it a lot better.
I might even use this tank for my race project, otherwise it will be a spare, or for sale.

A bit of old news

It's a bit of old news, but my camera broke, so no pictures for a while.
My dad and I went to the Ital-dag, even though I don't really have a close connection with italian bikes, sometimes you need an excuse to go for a ride.
Ralph made some pictures, also at the parking lot, and I really liked this one, the state of my dad's Oudshoorn BMW at the moment:

Behind it, my R90/6 joe-bar caferacer, compare the size.

Cool stuff.......oil, that is

I had this idea for a while, just been looking for the right parts.
Don't know if I really like the look, but it was fun to build, something unique, I mean, how many C110 oilcoolers have you seen?

CB72 freshened up

After last years season, the CB72 had its motor taken out because of a gearbox problem, and it pretty much sat at the end of the workbench for the whole winter.
A couple of months ago, my dad fixed the gearbox, and as we got the bike out of the corner, we did some slight modifications.
The rear wheel was swapped for one with an original hub, and a rim that matches the front. A front fender was made. (the dutch honda moped freaks might recognise it as a rare C320 fender) And the tank got some new stickers.

and the top yoke was swapped for one that has been welded shut and ground down to look like an original CYB yoke.

It is still a racebike, so it shows signs of use, but these little things just freshen the bike up a bit and make it look more like the honda's we all know from back in those days.

Kijima dress up kit for C110

Here you see my C110 Kijima dress up kit for the C110 engine I've been building.
Clutch, points and valve covers with some extra cooling capacity.

those of you who know the Kijima catalog are now questioning what this is, they are actually left side head covers for the OHC engines, modified to fit C110. Valve covers also need to be modified, or they jam against the rocker cover of a pushrod motor.
The motor I've built for Ralph also had these covers, it was his idea and I "borrowed" it for my own motor.

Didn't do much with the motor lately, as my SS motors kept givving me problems, but that is prety much over now, so I had time to spend on this little 60cc pushrod powerplant. It's almost ready now, just waiting for some special bolts and I want to do something special with the oil-line...to be continued.

clutch swapping

With the SS50 race project being for sale, the chance exists I could actually sell it to someone and I didn't really want to loose the Takegawa clutch that was on that motor. So I decided to switch it over to my 110cc engine.

Now the motor is rebuilt...again... with a 5speed gearbox, Takegawa clutch updated to 4 plates with some leftover china junk.

But that meant I had to start building a new engine for the racebike.
SS50Z cases, 5speed gearbox (and a spare 4speed close ratio) clutch moved to the gearbox input shaft by using chinese parts combined with a little bit of Kitaco, 85cc piston (allowed by the SAM) on a 12v crankshaft.
I have some plans for the head, but I'm not that far yet.
yesterday I did start on something for the breather, made it out of a CL72 filler neck that will get a bung welded on the rear to attach a hose.

It looks way high now, but imagine an upswept exhaust running just underneath that.