Wednesday, March 31, 2010


Yesterday the mailman brought me some nice presents, first a set of keihin CR carbs that I bought for a friend to put on his CB500t racer. Later, another mailman brought me my classic CB72 blinkers. I wanted these because of the classic model and they aren't as big as the original SS50 blinkers.
They are a bit bigger then I thougt, so they will probably go on my SS50 moped, and my SS50 motorcycle will get the ones that come off the moped. As my moped is bigger then my motorcycle :P

Sunday, March 28, 2010

SS50 muffler

Couldn't get my Jama muffler to sound right without major rebuilding, it is probably made for a twostroke engine, so I decided to go a different route. A long time ago I bougt a secondhand CB100 exhaust on ebay for 15,- now I cut off the header to use only the muffler on my C320 header.
Next to the Jama muffler, almost the same size, just a bit smaller at the front, 29,5mm internally where the Jama has a 32mm fitment.
Mounted; looks nice, a bit more like the original with the welds on the top and bottom.
Now it sounds like a Honda should, allmost exactly like our CB100, and I had my first testrun with it.
The 5speed gearbox is nice and close, only first gear is really short, made some adjustments to the needle to get it running better in the midrange, but that might change again when the engine gets run-in.


Didn't feel like doing anything on the 90 this weekend.
Last week I had an idea about an oldschool breather for my SS50 racing engine, based on the model of the CR110 breather. So I had a go at building that.
Original CR110 breather:

Picture thanks to J. van der Meer who made photo's of H. Mieth's CR110 at Schleiz if I'm correct.

My engine has a takegawa clutch, which has a fillopening with the same threads as the valvecaps. I used an aftermarket valvecap to make the attachment to the cover, on top of that I bolted a labyrinth, the M8 bolt has 6mm threads in the top where the cover is bolted to.

Mounted to the engine:

Tuesday, March 23, 2010

What it used to look like

Here some pictures of my SS50 moped, of what it used to look like in all the years I've had it. Many parts have changed in these last 10 years, but the frame is still the same one I started with.
First months I had a modified high muffler, that has been used a lot in the past years.
Changed the swingarm because it was rotten, to a widened C320 swingarm. also a different taillight.
Other seat, with metal tail. Wanted it painted to match the gastank in blue, but that never happened.
Didn't like the modern yamaha discbrake, got original forks and drum with BMW handlebars that were laying around.
Quickly changed the bars for a lower chromed type.
Note the custom homemade headlight with C50 speedo.

The headlight broke because the fixingscrew rotted in the threads and when I tried to loosen it, it cracked.
So back to my old yamaha steel headlight, now with CB50 speedo. And again the clip-ons. Also a dream50 taillight on an aftermarket rear fender, nice and small.
Changed the top plate for an alloy type from a CB100 with the handlebarmounts filed off.
And then the forks broke, because I had my brakeshoes lined with realy good material.
By now I had bought my CB50 with a load of parts, including forks and wheels, so the SS50 got CB50 forks with discbrake again. Not because I liked it, or because it was a good brake (it isn't) but because I didn't want to break more forklegs.
The front fork were too skinny, so fitted covers from an SS with headlight and speedo
Mounted an aftermarket SS50 front fender, needs some grinding and bending to fit to the CB50 forks, but still it looked like crap, because off the poor quality of the fender.
Found myself a CB125J front fender that bolts right to the forks, only needed a thicker front tyre.
Traded my long seat against an original short seat with metal tailpiece, rarer then rockinghorsepoo here in Holland. And changed the exhaust to a new extended dax exhaust.
Sold the dax exhaust within 500km, because I found an original semi-high muffler, used but only 15,- and some cleaning work to do.
Then the respray, and it looked allmost like the original 5speed model.
Wanted more of a caferacer again, so fitted fake clip-ons that mounted on top of the top plate. The seat is an original K1 short type, still had the one with tailpiece, but my girlfriend wanted to ride along. Front fender was copied from the cb750 out of the "Joe bar" comics. And note the dream50 taillight was swapped for a real old one.
By now I had enough of crappy discbrakes and wanted a drum again. So a full rebuild after the winter. Older style front forks, without rubber parts, aluminium headlight with inbuilt speedo, small blinkers and many freshly painted parts together with the old wheel from my CB50 racer.
Didn't like the long tank with classic forks, so changed it for a CD50 tank with aftermarket seat, had to change the mounts on the frame to have this fitted.
Different swingarm with full chaincase, for the classic look.
And to make it a bit more sporty, the handlebars were swapped for another set of fake-clipons, homemade and lower that the old ones I had.

Sunday, March 21, 2010

Passed the test

We went to Leerdam today to have the 90 looked over by the CRT club officials who determine what gets allowed onto the tracks. Not to much rules to follow here, just that it needs to be old enough and that it looks like a racebike from the past. No discbrakes, no space-age materials.

Some pictures of the day:
My bike unloaded, quite a lot of other people bringing new bikes.

A honda CB250 or 350, still needing a lot of work, but with some nice period aftermarket finned points covers.

CB72, also with some work to do, but a real 60's honda. Still in the van, next to a Ducati that was completed.

Triumph sidecar owned and raced by Ella and Stef, Ella used to be the passenger in my dad's sidecar outfit, now she will be riding this, with her boyfriend as a passenger.

Nice Ducati

MV Agusta

And a real nice NSU, sheetsteel frame and leading link front forks, lots of beatifull small details. I like bikes that are a bit different then the general idea of what a racer should look like. (tubular frame, ceriani forks and a factory twincam or two stroke engine)

And what it was all for, the decal on the headstock

My bike is allowed into the club. Now just a lot more work to get it finished, but at least I'm sure it will not be in vain.

Saturday, March 20, 2010

Picture day, part 2

And the CS90RSC was also out for pictures today, need them for tomorrow when it has to go for scrutineering to have it allowed into the club. It's not finished yet, but you can see what it is going to look like when it is done.

One more picture of the rev-counter, spot the latest addition.

Picture day

Had my SS50 project out today, most parts are new or newly painted/polished and the engine has only given its first signs of life after a full rebuild. Needs some adjusting to the muffler to get it running correctly and with a nice sound, then I can start riding it when the weather is better. Frame is SS50M and is registered as a dutch motorcycle, engine is a 5speed SS50 unit, all original.

Don't look at the CL70 framecover, it will be painted to match the frame, but for now I can fit a larger battery then would be possible with an SS50 cover.

In the future I want to change it some more, with alloy fenders, long tank, short racing seat, ......but for now it's just about roadworthy.

Friday, March 19, 2010

Drum brake

My dad does a lot of drum brake overhauls, mostly skimming drums and relining brakshoes, but recently he has also started repairing cracked drums. He has been riding BMW's for about 40 years now, and they have a problem with cracks in the cast iron lining of the drums. Moisture and dirt collect between the aluminium and steel, it oxidizes and the steel gets pushed inwards.
Here is a drum that has been turned on the lathe to cut out the lining, which came out in one piece.

Obviously this has a negative effect on heat transmission from the steel to the aluminium, causing the lining to overheat.
This drum will be prepaired to fit a new cast iron lining, here are two drums that are allready done.

The holes in the right drum are not standard it used to be in a race-bike.


Made the cables last week, brake cable had to be shortened as it was probably an aftermarket cable for a CL175 with high handlebars. The clutch cable is made from something I think is original, only had to shorten it a little bit to fit the aluminium adjusters. Brake cable is of a big diameter and fits perfectly into the adjuster, the clutchcable has some room, but that makes it easier to get it thru the tight space around my clip-ons.

Also note the original wire band arount the front stay that keeps the rev-counter wires in place, no modern zip ties for this bike.

Wednesday, March 17, 2010

Australia connection

Some pictures Stew sent in from Australia, he is also building an RSC90, only the earlier type with the teardrop tank. He had it replicated from pictures.

He also ownes a great looking original S90, candy paint and chrome fenders, never seen those over here.

And his CYB350

There are more bikes and projects, all as nice as this.