1010cc cafe racer

JohnGoodenough

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Location
Johannesburg.
Hi guys
I bought an xs from a guy about 6 years ago, and hardly touched it.
I had 6or 7 two strokes that I fiddled with and raced.
Eventually had to sell everything :-(

Went back to the guy I sold the xs to, and he sold it back about 6 months ago.

Had always been difficult to start, and the starting rollers at the track days was the only real chance.

Always knew it was something special with the halco tuning badge.

Decided to build a cafe racer, so for the first time ( in my hands ) the motor came out.

Careful measurements tell us 95mm stroke and 87.5 pistons.

The motor was done in Johannesburg by a guy who would fly to halco in the uk with cranks in his hand luggage!!

I'm now going to try post pics..
 
The album in your profile shows the combustion chamber with the compression release. It appears that you have ground a considerable amount of material from the chamber and rendered them useless my opinion. It is a very bad picture. A better picture would help. Also no pictures of the pistons and cylinders. :shrug:
 
Hey, John. Went through your album pics, your album is okay. Quite an engine. One pic of piston with your tape measure looked like 83mm? Pistons look pretty scuffed, rods have the euro '533' long rod marking. With a 5-6mm cylinder spacer, and 7.9-8mm camchain pitch, I wonder how camchain is setup...
 
The bore is perfect.
Piston's not as bad as it looks. I think they must have put 2 extra links in the cam chain?!?
I suppose I can count the links...
Spacer is 8mm
Bore is 87.5
What do you by cam chain pitch?
Thanks TwoMany
 
The blue buttons are off a husqvarna chainsaw. Starting this beast was simply dangerous.
Seriously going to get a probe ignition, along with good battery cables.

I first found a '74 decompression setup and mounted it, but was still dodgy.
Kicked me back. Hard. And electric foot stood no chance.

So I took the head to an engineering shop it install the husky thang, and they put it on the wrong side! Hence the second one!

I've spent days polishing parts, and early January the grinders will grind, the powder coaters will coat and the builders will, well, build!

Dyno tuning to follow.
Compression ratio is 10.1
 
Hey JohnGoodenough,

I can't get my head around how you fit a 95mm crank in there.
The stroker crank you have looks like a modified stock crank, which makes the OD 130mm.

Here is a photo of a stock flywheel with a 533 rod placed at 47.5mm from center (95mm stroke.) you can see that the big end hangs out a fair way past the edge of the flywheel.
null_zps52791fc5.jpg

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533 crank pin sitting 3mm away from the edge of the crank:
null_zps36f0c0b2.jpg


This image of your crank shows the big end sitting pretty well within the diameter of the flywheels.
null_zps03f829f1.jpg


A stock 74mm stroke crank with 533 rods and TT500 pistons which you have, all fits in nicely with no spacer required (some piston machining required).

If you have an 8mm spacer fitted, then I guess the crank pin has not been moved more than 8mm which would leave you with 90mm stroke. 95 could still be possible with an 8mm spacer, but the pistons would have to be trimmed up real short, use a thicker head gasket etc.
Then there is the next problem- the big end of the 533 rod measures 51mm (if you shaved the ridge off the outside) this would require 146mm of clear space around it to rotate in. My crank is 138mm OD and I had a hard time fitting it in- had to remove a bit of metal here and there.

Not saying it is impossible, just looks unlikely to me.

Cheers,
Matt
 
Hi Matt
I have no doubt that you have much better knowledge than I ever will regarding such issues.

I really don't want to split the cases, but I will get a vernier and measure the full piston travel when I put the barrels back on.

I hope I haven't made a mistake here.

Vernier will tell.

Thanks again Matt
 
Looking at pics #15 & #20 in your album, could the stroke have been measured from the top of the spacer plate at BDC instead of the top of the piston? It looks to me like the amount of piston sticking above the plate could be about 9-10mm higher than the plate, which would account for such a radical measurement. 95mm - 10mm would be 85mm alot closer to the bore of 87.5~. A similar ratio to the original 75mm bore x 74mm stroke. :twocents:

....What about measuring the ring wear marks in the cyls?
 
Either way, it's still a monster even if it is ONLY 1050cc!

1100+ is possible, I have a friend in France (coincidentally was friend/rival of the late Tony Hall) he once built an 1130cc or similar. The rods hung out the side of the crank so far that he had to leave some parts out of the gearbox just to fit it in! The thing made over 130 hp on the dynobefore it exploded. The rolling road had to be pulled apart to fish out all the pieces. Needless to say this gentleman was no longer welcome back at the dyno shop!
 
Hi Matt!
Thanks so much.
I will check properly when the barrels are back on.
Bit embarrassed actually!
Shouting out about the biggest ever and then maybe not!
:)
I'm about to order the probe ignition from them directly and coils and a few small items from Mikesxs.

Really excited, and thanks for the input! Will post as I go.
John
 
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