home made rev counter stuff

The plan: build a mechanical tacho and tach-drive onto an SS50 engine.
terms: do not use kitaco or takegawa bolt on stuff.

I started with a tach drive from a CB175, turned something on the lathe and took the teeth off of an old camshaft sprocket, this should be soldered together with silver and mounted to the camshaft.

should look like this when mounted:

The housing was cut down to remove unnecessary material and to create a hole for the bolt to go through that will hold everything onto the cylinderhead. A brass plug will be put in there with threads to accept the bolt.

One problem, on a CB175 this is on the right side of the camshaft, on the SS50 it will be on the left, so the tachocable will be turning the wrong way.

On the back of the Yamaha 600 guage unit (that I took the tach from for the RSC90) was an angle drive that I could use to reverse the rotation...

Some PVC tubing, a CB50 tach and one Yamaha drive later:


Testrun if it all works...NO?...
I looked at the angle drive the wrong way, so it doesn't actually reverse the rotation.
I will have to make something else to fit onto the modified CB175 drive and use this tacho on another bike when it is finished.
Will be painted black, alloy ring to be turned on the lathe and a piece of plexiglass to close it all up, after I've made a new face for it, probably upto 14000 RPM or a bit higher.

Caferacerdag

Today the dutch caferacer club had a meeting, so I decided to go and have a look.
It was a nice excuse to take the BMW out again and my dad came along with his Oudshoorn BMW, although not totally complete yet (notice the seat) it was a nice ride to run in this newly built 700cc engine.
The bikes before departure;


The oudshoorn looks small next to my R90/6

To see more pictures of great caferacers that attended, look at the chalopy blog Ralph was there too and took a load of pictures.

RSC engine cover

Look what came in recently.
Specially made in england by a great guy called Colin Marley.

Original next to CNC milled, I glassbeadblasted mine to match the rest of my engine, and for some extra cooling surface.
Here is what that looks like when mounted, sorry about the fuzzy picture.

Some of these will go to Australia (you know who you are) but I haven't figured out the shipping yet. There is one extra if someone would be interested.

Hondaday today

Today was Hondaday, the yearly gathering of the dutch honda moped club.
In the morning the weather was almost clear, so I thought I'd give the SS50M a ride to completely break in its 70cc engine.
I totally forgot to take pictures, but Ralph will probably put some up on his blog.
Spoke with Ralph for a while about the C110 engine I am restoring for him and the S90 parts he borrowed me. Had a look around the lot, spoke to some other people too and then went home again.
But only after I had the SS50/70 on the dyno. The Honda club had arranged a free dyno for everybody to try their bikes, so I couldn't pass that up.
Graph seen here with some great pictures from Mischa who brought his 1970's polaroid camera.

About 6.5 HP at the rear wheel, not bad for a 70cc with 20mm carb, with a top of 115km/h.
The bike is now totally run in, so it's time to start looking at the 26mm carb that I would like to put on it.

The right tools

Finally my tools are in.
Original Honda crossheaded bolts are different from philips or regular crossheads So I ordered the original Honda workshop tools.

This is worth the money, it really makes working on your old Honda easier.
If you want to order them too, the Honda partnumers are:
07603-0050101 for M5 and smaller bolts.
KL1696 for M6 (engine bolts)
It did take a while because the big size was in backorder for a long time, so be patient.

Lots of racing this weekend

Yesterday we had a race in Nunspeet, I had a lot of trouble getting the RSC running correctly, fiddeling with main jets, but at the end of the day I found the right one. All the symptoms directed me to a bigger jetsize, but smaller was the answer.
I did have a lot of issues with the gearbox though, after the clutch exploded, the gearselector arm was bent.
Pictures can be found thru the Nunspeet bike club website (click "classic race")
What do you know, If you click the 2nd link, the first thing you see is me....

picture thanx to: www.naomischolten.nl
More great photo's can be found on her website.

My dad rode his CB50 with 75cc engine, also having gearbox trouble, first time an original honda 5speed doesn't work the way it should, they are normally pretty indestructible.

My RSC engine was opened up today to fix the gears and it seems to work a little bit better now.
So the RSC is allready on the trailer again for races tomorrow in Varsseveld.
I didn't want to ride the 250 or 500 there, so we got my CB50 out and put it back together again, as some parts were "lent" to other bikes.

I hope tomorrow all goes well, the 90 gearbox should show improvement and the 50 has an experimental camshaft setup.

Cam timing

The trick to timing your cam the way you want to:

Extra holes.
In fact this isn't my camshaft I'm now using, it is Ralph's But we now have it timed for more power at higher revs.
It was probably made for dirt-track or motocross, probably even for ATC's where you would like to have power in low revs, but for roadracing this could be cranked up to about 11.000 RPM.
I don't want to go much over that, just because of reliability and gearbox limitations.

New seat

Bought a new seat for my SS50 off ebay.
The old one made the whole bike look very dark and chunky, with a fully black seat with black piping.
This one has a nice "chrome" edge and its a little thinner then the old one.
It is aftermarket, but you just won't find originals.
And this one fits, unlike the aftermarket stuff sold in the Netherlands or the expensive benly seats that also won't fit with a CD50 tank.

Note the breather, just like his RSC90 big brother.

Anjum

The third event for the RSC90, it was repaired just in time after the clutch thing.
Carb was temporarily replaced with a CB100 part that we knew was working, also the coil was replaced. These were the parts that were doubtfull, so we eliminated them.
A shot in the paddock:

You can see the CB100 carb mounted on an original manifold.
After the training we put in a bigger main jet, it ran pretty well, but the plug was a bit light.
Just one round in the first heat told me that was wrong, I came in, we tried to change the needle position in the hope we could get some progress and I could back on the track for the remainder of the heat, but the clip fell off the needle in the grass.....damn.
But at least we knew now that the bike could run good, and the problem had probably been the coil.
So we put the CR29 back on for the second heat, and it ran pretty well, needle and main jet being allmost right.

Also note the alloy top crown plate from my CR110 replica forks, this was to get less pre-tension on the front forks, a step forward to good handling.
close-up:


A shot from the paddock:


Me in action, must have been the second heat, as you can see the CR29 mounted.

picture thanx to Lea our club photographer.
more pictures of the event can be seen here

the clutch

....or what was left of it, after we fished it all out the engine.

Note the elongated springs and warped clip.