A possible earner ?

Joined
Jun 30, 2012
Messages
13,128
Country flag
After getting involved in Bernhard's wideline frame debate, I've decided to put up an idea I've had for a long time, which I cannot afford to pursue. In Australia we have juniors racing in which Honda CBR150s and Metrakit 80s are used, cost up to $10,000. We have bucket racing which involves four stroke bikes up to 180cc, and two strokes up to 80cc. We also have historic racing which involves CB125 Hondas and 125cc two strokes. I've looked at the Chinese CT110 Honda clone pit bikes, aermacchis and this bike which was built in the US, and I think there would be a market for a frame kit to build an aermacchi style bike. It would de pend on how various race classes are constituted and promoted. I believe any two stroke would kill such a bike in competition, so the class would need to be limited to fourstrokes up to 180cc. The bike in the pics is actually faster than the two strokes, but it uses an emission control air pump off a car as a supercharger.


A possible earner ?


A possible earner ?
 
There you are, a nice and easy little project to learn on. Use a Yamaha TA125 tank, and a Honda seat - instant classic racer/bucket/ juniors bike. And you can get almost anything for those motors including DOHC 4 valve heads , and 6 speed CR gear boxes, and heaps of hot-up stuff. I bought a whole secondhand bike with 125cc motor for $50. If you were smart the frame could be made to also take a Harley Sprint motor, as well as the chinese motor with plates.You could build it to look like this :

A possible earner ?
 
I'm impressed. Do you have a pic of the whole bike Acotrel? Those Takegawa engines are the biz too.
 
I have a Takegawa DOHC kit fitted to one of my Sachs Madassbikes, thing revs like a 2 stroke, but Takegawa parts are very expensive. I'm planning to use the motor or at least the top end in another long term future project , getting a 5 or 6 speed box for those little Honda engines is very hard. bit off track but I have a 6 speed tranny to go in my Skyteam Ace 125 (CG125 based engine)
 
Nothing new under the sun, as there was and still is a Bantam racing club in the UK which raced those cheap little BSA 125s, until the Post office bikes started to dry up. Then they went for the class MZ250s .

http://www.bing.com/search?q=Bantam+rac ... ORM=IE8SRC

The supercharger engine has been banned for motorcycle road racing by the FIM from, I think late 1940s, early 1950s.
 
I raced against a modified bantam in historic racing . It was about 200cc and full of yamaha parts, fitted with an expansion chamber. My problem is in reconciling the word 'history' with a bike like that even though it fitted 'the rules'. The point I am making, is that a fourstroke class using Chinese CT110 clone motors won't be destroying bikes which should rightfully be restored. And there is so much potential for tuning, and development - relatively cheaply. The bike could even be construed to be 'historic' - it could have existed. Imagine a field of fifty such bikes in a race with no two strokes to upstage them. I suggest we would actually get real racing.
 
I am sorry that I don't have a photo of the complete bike. I thought the web page with the article about it would be there when I wanted it, however I couldn't find it again. It was very detailed about how the bike was built.
This frame kit is the metisse version for the aermacchi. Anyone who built the kit for the Chinese motor could get the whole bike built in China (perish the thought), however I think we would all have a lot of fun with this.

A possible earner ?
 
If you had one of these in the old days before the tw o strokes really got going , it would have been the ant's pants. I cannot see why we cannot take a step back and have a race class which would encourage constructors and give really good competition. 'What man has made , man can make again' ?

A possible earner ?


A possible earner ?
 
You need to make a frame jig with a pivot to hold the head stock, a strong base channel to hold plates to locate the ends of the swing arm pivot. I bought a couple of lengths of pvc conduit, a spring for bending it and a heat gun - we have computer tube bending available near to us in Victoria. If you make the head stock out of strong material, you would need to bronze weld your frame to stop cracking , and it is better because the fit-up is not so critical.
 
" The postie bike is too difficult to turn into a racer"
I agree but they are making these laydown engines now with 20-25HP so a new door opens, finding a place to use that engine, I have my own ideas which are not disimilar to what your original post is about.
Although regarding your comment about postie bikes not suitable for racing, here in the Philippines they race
these things, well they are what you and me would call scooters but they are better than an old postie bike.
Suzuki have one, Raider 150, the engine is virtually a slab off a GSXR engine, DOHC, oil cooled pistons, 6 speed tranny, a few mods and they go like shit.
 
I realise that postie bikes can be raced, however they will never appear to resemble a classic road race motorcycle such as a CR93 or an Aermacchi Ala D'Oro or an MV Bialbero. I think that is sad because those bikes were things of beauty. I also realise that Vespa motor scooters were raced, - that did not last for long. I suggest that when we do that stuff we might be selling ourselves short, and missing an opportunnity to do something really good. I might be a bit strange, however I've seen what excellent road racing looks like. These days I cannot even watch what we call historic racing, because of the inane mixture of bikes which runs in most races.
Imagine a race grid of forty bikes resembling the CR93 style, but with Aermacchi style frames, Takegawa engines, fairings, rear sets, clipons, race tanks - all sounding the same with pretty much the same power output and handling. For someone like myself, it would be heaven.

I believe that the Sachs Madass is built from an Egli frame, even that would be better than a pressed steel postie bike frame. I don't know how a postie bike can be made to look right as a road racer. It gives me no joy.
 
Back
Top