4 speed close ratio gearbox

Decided to take some gearboxes out, known for not being so good, S50 and S65, combine with a little SS50 and some more modern parts, and create another 4-speed close ratio.
Not as close as the racing gearbox, but nice for a spare racing engine, or any other future build.

13-35
18-29
21-26
23-24

when installed in a racing engine, I might even replace 1st for a 14/33 or 14/32 with long shaft for mounting a clutch.


Seen in the picture, the special tool for shimming the gearbox and checking if all the gears line up correctly, a must when combining things like this, as only the 4th gear shift drum really worked for this setup.

replica CR93 parts

So busy, and forgetting to update, so here's a quick one

Original parts were borrowed, and copied 6 times.
Replica CR93 foot rest brackets, in raw form.

clip-on's

Just finished a batch of clip-ons
Needed a set for the SS50 racebike and another for one of the CB50's that has been sold, but included in that deal was a front end swap.

A bunch of steel pipes


Some more small parts added, almost ready for brazing



after brazing, cleaning and painting


The observant viewer would notice one set missing, that was already mounted to a bike.

Some details not found in modern clip-ons are the closed ends, not with a plastic or alloy bung, but full steel construction, so that after painting, it is almost invisible how the ends were closed.
Just a single 8mm bolt, instead of 2 6mm bolts, just like original CR110 clip-ons, and other Honda's from that era.





Took a lot of work, but the result are some clip-ons that look deceptively simple and yet sophisticated at the same time.

CR lookalike

Just a preview of something I've been working on.
A Honda CB500f carburetor modified to work on a one cylinder bike and with some styling like the old CR carbs.



Still needs finishing and testing though.

engine stands

When working on engines, I used to use some wooden beams, but they always slid away.
then in the new workshop, I made an engine stand from some leftover bits of hardwood, and this worked so well for me, that I wanted some more, as I get more engines to work on at the same time now.

Today I made three more engine stands, with some slight differences, hardwood, so they don't damage what you're working on, but sturdy enough to be able to use an impact driver, and high enough to put a small oil catch can under it for draining engines.

In the picture demonstrated with some C110 engines and a (customer's) S90 engine

freshly built SS50 engine

Just finished myself another engine. classic looks on the outside, but with power inside.

looks like a very early 5speed ss50 engine


extra mounting point in front on the cases and no engine numbers




Made this way with modified S65 cases, fitted with 52mm stroker crank, 52mm cylinder making 110cc, with a ported CL70 head, fast camshaft, 2 plate alloy clutch coupled to a modified original Honda 5speed gearbox and many more modifications and rare 60's parts such as the engine covers and breather kit.

CR750 clutch levers

almost finished
just waiting for some levers with rubber tips to fit in the other 2 hand made CR750 perches

-sandcast perches machined by hand
-stainless lever bolt, to original measurements (unlike some other replicas)
-stainless pinch bolt
-stainless spring
-stainless spigots
-original lever with rubber tip

CR / RC style levers

After moving to a new workshop I'm aiming to expand my production, now tooling for making complete CR / RC style brake and clutch levers.
I've already made perches, but just now I've tested my prototype home made lever, quickly machined it to work as original, mounted to an original perch and squeezed with all my might....and it stayed intact :D
That makes it possible to remanufacture almost all the parts so I'm not reliant on NOS parts that may or may not be available. Now to work out the last bits before production can begin



also check out my facebook page

tachometers

Since I've built a new tacho for my 50 this year I got annoyed by the quality of the old prints for the tacho face. So I asked a friend who is good with graphics and has his own company in printing if he could help with new tacho faces, not only the CR110 / CR93 replica, but also an RSC and two different smiths faces, like the ATRC tacho's.
Today I mounted the first test print into an old housing to see what it would look like and how it would fit. Just a few tweaks and then it will be ready for a small production run.



also available will be:
smiths from 1 to 14
RSC from 3 to 15
CR110 CR93 replica 3 to 16

all to fit in original honda 1:7 tacho's as used on most models up to 500cc

another batch

And yet another batch of brand new vintage parts.
Including two of the newest project, a rear backing plate for 110mm Honda hubs, SLS but also in the future I plan on making a 2LS out of it, some preparations for that are already in the mold.
Planning the 2LS for my RSC90, will make the rear hub fit more with the 4LS front CB125RSC hub.



the line-up:
160mm front brake plate, Honda RC styled
110mm rear brake plate, Honda RC styled
CR110 footpegs
CR750 clutch perch
Honda RC styled brake pedal
JRP breather covers
S-monkey oil cooler adaptors
RSC engine cover, meant for a Honda 50, but going towards a 750

CB72 racer

Had one of my dad's CB72 racers out to testfit a CR93 fairing that I have for sale, someone wanted to know how it would fit a CB72.



Fits it quite nicely I would think.
And then we rearranged some of the workshop, what meant that another CB72 came out of a dark corner, making me want to start this project.



Not with original tank and (replica) CYB seat as seen here, but with something more like a CR72 tank, period correct and with a lot of home made castings and other replica parts, and even some originals. As I have collected some CYB72 stuff over the years.
I have, or can build many of the small parts, the tank will pretty much be the only part I really don't have any idea of where to find or how to built yet.

picture day

Not bikes this time, but parts.
homemade cast aluminium parts.

Honda CR750 pedals


Honda RS125 / RS250 foot pegs


Honda CR110 pedals and pegs


Honda MT125R top yoke


Honda replica brake plate for 160mm drum


Honda CR110 / CR93 perches

(in machining all evidence of mirror mounts will be removed, better then plugging one up or welding it shut)

JRP covers for sale, part two.

the top engine covers / breather kits are also ready now
for sale as a set with the points cover or separate.



interested?
cb-viguur@hotmail.com

only 10 to 12 breather sets will be made

JRP covers for sale

I've now got 5 JRP points covers for 6v monkeybikes machined and ready, but I don't have that much engins myself, so some are for sale, if anybody is interested, give me an email.



I'm also working on the top cylinder head covers / breatherkit, but they are not ready yet. Will be available soon, and also as a set with the points cover.

2 more days of aluminium casting

Last week, I planned two days of casting and managed to create some more nice parts



some Honda MT125R top yokes, CR750 pedals and shift arms, CR110 pedals and pegs, also useful for other Honda racers like RC162, RC181, CR450, CR72 replicas and so on.

Another 160mm TLS front brake plate and a bunch of JRP engine covers for monkey engines, most of which are already reserved for friends.
Guess I'll have to do some more casting...

tachometer

Okay, last weekend was another event, and again I forgot to take pictures, the day is pretty full when riding 3 classes and doing repairs in between.

The RSC90 had a brake problem in training, so I swapped the 4LS wheel for the spare 2LS with homebuilt brakeplate, which performed perfectly.


(picture from the CRT website)

The C110 did really well, only the brakes leave a little to be desired, might be they are too small, or that I can't get enough force into them, so I swapped the brake lever for a longer one to see if that will help for next weekend.

And then there was the CB50, took a little getting used to, as it revs much higher then the other bikes, and now found it annoying that the tachometer wasn't accurate anymore since I had fallen some time ago where the tach had some damage afterwards.
So finally I decided on making another tachometer that would be accurate even in those high revs. and the old one from the 50 went onto a CB72 where it is no problem if the accuracy goes down above 13.000rpm.

Step one, take a standard Honda tachometer and open it up.
Step two, make a little bracket that stops the needle at 3, or whatever you make your custom face start at.


Step three, replace the face, and paint up all the outside bits to the colour of your choosing. In my case black, like the original CR110 tachometers where my face is modelled after.


Step four, put the tachometer back together again, seen here still resting in the cilinder liner that has been modified to become a tach-pressing-tool to crimp the original ring closed again.


and in between, check if it still works okay, these things are delicate, I'm glad this one went well, and also like the completely white needle and black surrounds, the first ones I did were different, but I like this better. Less fuss, more pure racing use.

spare wheel

The spare wheel is pretty much done, just a screen to make in front of the scoop, tested it in my SS50 motorcycle and everything seems to work just as it should.
Testfitted to the RSC90 and the brake anchor fits as it should to both the S90 and CY50 forks that I have in these two bikes.



not a bad look either, but as it only a 2LS, there will be torsion in the forks, which I don't want.

New front brake for the RSC90

With the S90 forks I've had the issue that under braking, the forks twist with the single sided brake. It's not a big problem, but it just doesn't feel that confident.
So what I wanted to do about that, was to create a double sided drum brake. As a test for that I started the homemade 160mm single sided brakeplate to see if a homemade brake could be up to my standards as for rigidity of the plate and so on.

But then I found something online in Japan: an original CB125RSC front brake

It took some time and effort to get it over here, with thanks to the great service of Masato But I got it, a real original NOS Honda 4LS front brake. Dreams come true.

This would become my new brake for the RSC90, a fork brace would have been a lot cheaper to stiffen up the forks but no way as cool as this.
So I started on making all the other little things needed to fit the hub, like the cable splitter:


machined it from billet aluminium, from pictures of the original CB125RSC and RC166 splitters, I just kept it a little bit smaller to match the tiny build of the S90.

I had spokes made to fit my 18x1,50 DID rim so the hub could be laced up.

ah look how beautifully tiny the hub is, only a 130mm but 4LS, making it cute and tough at the same time.

Making brake anchors out of aircraft grade aluminium


And as always, the last step is to make the cables, made from 2 original grey ss50 brake cables that were discoloured just a bit so they match the other cables.


and the endresult, including my newly built bigbore stroker motor:

Brakeplate

A while ago I found a new brake for my RSC90, that I'm now in the process of fitting (pictures will follow) but the old brake has come out and I've also started machining my self cast brakeplate to fit that hub, so I can have this as a spare wheel.



Already starting to look like a real Honda racing front brake :D

close ratio gearbox, finally complete

My RSC90 is also on the workbench again, hopefully to have it up and running for next weekend in Varsseveld.
The last time I rode it, there were two things that bothered me:
- the footpegs / groundclearance
- the gearbox

As seen before the footpegs had already been changed, but the gearbox was still an issue.
It had problems shifting from first to second gear, ending up somewhere in between, halfway in neutral but totally stuck until you would kick it up and down a few times and finally end up in second.
And besides that, the gearbox had been changed into a close ratio box, except for first, what meant I had a huge gap between first and second.

So now, I opened up the motor, to finally have first gear altered to achieve a full 4-speed close ratio gearbox as near as I could get it to the original RSC90 gear ratios. While in the meantime altering the shift forks hopefully getting a smooth transition from first to second.

I had already found some gears that could become a first gear in the S90 after grafting them onto S90 parts and my dad made it a reality.
My gearbox now has an SS50 second gear made into an S90 first.
Together with the SS50 3rd/RSC90 2nd as a second gear,
original S90 3rd
and CT200 4th gear
it makes the following close ratio gearbox:

1: 17/31
2: 20/27
3: 22/24
4: 24/23

compared to original S90:

1: 13/33
2: 19/29
3: 22/24
4: 25/22

and original RSC90:

1: 18/30
2: 21/27
3: 22/24
4: 24/23

clearly visible, the difference between the stock 1st gear on top and the diameter of the modified shaft.

Also swapped the crank for a different one, because this motor had terrible vibrations, maybe this could be the solution.


Now to finish the motor and get it back in the frame and I'll have to check everything as a lot of parts had been taken out or used for other bikes in the meantime.