Better than any Triton

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acotrel said:
The bottom end from a Japanese V twin might even have a strong 6 speed box attached.
If you select wisely, this could come attached to quite a powerful motor.
With alloy beam frame, good brakes, fuel injection and upside downies/ohlins suspension.

HD and Buells also have such things these days...
 
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I think it would be interesting to fit two top ends from lay-down Jawas to the bottom end of a six speed modern Japanese V twin. I'd still run it on methanol, and use it for track days. It could be a real hoot, and not extremely expensive ? There have been V twin sidecar motors made from single cylinder speedway engines on new crankcases, none with the wide angle Ducati setup. The Buell was a good attempt at making a decent V twin, however except for the S1, the frames were pox. With a narrow angle V twin, how do you avoid having the carb on one cylinder hitting the head on the other ? I think it would be impossible to find two XR750 heads these days.
 
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acotrel said:
. With a narrow angle V twin, how do you avoid having the carb on one cylinder hitting the head on the other ? .
With water cooling, and not worry about it ?

There are plenty of performance 8 valve v-twins around, why re-invent the wheel ?
Just buy one new out of the showroom, with warranty.
Duc even make little ones ?
 
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The speedway Jawa engine is a racing engine, not a road engine. If you can look inside one and find a way of making it faster, you are a better man than I am. Ducati or any other factory wont sell you anything like that top end on a road bike.
 
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acotrel said:
Ducati or any other factory wont sell you anything like that top end on a road bike.
Ducati will sell you an 1199 with just shy of 200 bhp, as a road bike.
Reliably.
With warranty.

If you can get anything remotely like that, reliably, out of a cobbled up bitza engine, you are in the wrong business.
 
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At what price, and what are the maintenance costs ? My friend had a business servicing Ducatis. No bill was ever under $5000. Most of his work came from guys doing it themselves. He'd pull the motor apart in front of them to justify his charges - so no arguments. Have you ever seen the head from a modern water cooled Ducati in pieces? It is horrific. A SOHC jawa head is a much simpler answer. And you wouldn't have the weight of a radiator to drag around.
 
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5k servicing costs?? Surely you mean $500 ? Utterly ridiculous...somebody's lost the plot!
 
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It would usually involve repairs. The bits are really expensive. Most of his customers bills were over $5000, and most of his work was fixing other peoples' stuff-ups. He was the guy who got Kevin Magee through his crash and burn stage of racing with an 851 Ducati fitted with his own four valve cylinder head. It is the only four valve air cooled Ducati that I've ever heard of. It was sold to the Japanese collector.
 
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In the mid 70s I had the opportunity to get a Weslake 500cc grass track motor. The plan was to convert it to dry sump instead of total loss, and drop the comp ratio so it would run on petrol. Then install it in a rolling slimline Domi, that had been burn't out....damn fibreglass tanks. Sadly after doing a lot of the preliminary work (finding out if it was feasible, getting information from weslakes etc), the motor went in another direction, not to me. It would certainly have been a goer though.
It was at about the same time that my brother and I were working on a Hillman 1200cc Rally Imp engine in a roadgoing, featherbed framed, single seat sidecar, we had sourced the leading link forks, and 16" wheels. All this so Chris (my brother) could take his beagle away camping with him!!
cheers
wakeup
 
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So did you build a Norimp ??

While in theory these sound great, thats not a vast power output they produce.
And thats not the prettiest motor around either.
Full fairing may hide it, and speed it up somewhat, of course.
 
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Rohan said:
So did you build a Norimp ??

While in theory these sound great, thats not a vast power output they produce.
And thats not the prettiest motor around either.
Full fairing may hide it, and speed it up somewhat, of course.
Sadly no. We had all the big bits (engine, gearbox, frame, forks etc etc) All the bits had been balanced in the appropriate place in Chris' garage, with help from the beagle. Then Chris and his then wife separated and later divorced. I have no idea where all the bits went. Knowing his first wife they went in the skip.

The outfit was going to be similar to one that was being raced locally, but with a single seat chair, rather than a platform and the obligatory street equipment. The motor certainly was not particularly attractive but at least it was all alloy!
I've just had a look at Wikipedia and found that the "standard" rally Imp engine was 1,000 cc, and produced 65 to 70 bhp at 6,200rpm and 62 lb/ft torque at 3,200. Which back in the 70s would have made a very sporty outfit, for a man and his beagle!
cheers
wakeup
 
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What was the air cooled four cylinder car engine which was used in sidecars in the 70s ? NSU ? I've got brain fade.
 
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