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Discussion Starter #1
Anyone know anything about the Ascot/Shadow 500 motor? It looks pretty compact in all dimensions except maybe height. It is cheaper than an NT650 motor yet very similar. Can this be easily converted to chain drive by pulling the angle drive? Any particular problems with them? I am wondering because there is one locally that I can get pretty cheap and am thinking of eventually building my own frame (stupid Foale book) and wanted to start looking for a good donor engine to build the bike around and wanted something different.
 

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Discussion Starter #2
Anyone? Bueller?
 

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ken essex is our resident ascot expert. I'm sure he will chime in.

The Tony foale frame seems to work best with across the frame inline fours since you can slope the tube downward past the head and not worry about running into a second cylinder, unless you had some crazy idea about bending the backbone a la confederate or R.E. engineering.
 

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Discussion Starter #4
I wasn't planning on building a Foale frame, per se, but I was inspired to build my own because of his books. I've got a few crazy ideas. I may build a Ducati-style frame, or it may end up with a Hossack front fork or something crazy like that. I may even play with giving it a CVT so wifey can ride it. I won the auction for $6.50, so I am prepared to take a chance with the motor, but if anyone tells me that it is shit, I can just pay him the money and tell him to keep it.
 

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There is nothing wrong with the v-twin Ascot, other than it is shaft drive. I don't know of anybody converting it to chain, but it did not have much annoying drive line lash, so I would go ahead and use it. The Shadow had a 16" rear and the Ascot had a 18" rear, so you would have some choices there. Back when I was in the business we almost never saw any of the smaller twins in for repair or service. I think it would be a fine first frame project since the drive train is already fixed in place.

Ken
 

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always take the motor - worst case scenario is you can build a chopper or a flattracker out of it, or power a go kart, or make a generator, or......well you get the idea.

You want something really unique - go find a mid 1990s ninja 250 and drop the ascot motor in that, it will make more than a few ducati and hd guys turn their heads to see a v-twin powered sportbike.
 

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Discussion Starter #7
Well thanks for the info. I may just keep it a shaftie, then. What really made me think that it could ba a chain drive is that all the NT motors are, and there is a guy in ebay that has a sprocket cover listed for a VT500, which shows a sprocket along with. Now, I did not initially believe this was correct and thought maybe he meant for an FT Ascot, but all of the other parts he has are for a VT ascot, so maybe I'll throw him the $5 just to see.
 

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Discussion Starter #8
Good ideas, Geets. I bet I could find one of those ragged out Chinese "sportbike" frames and hang that thing in there for street legality, then fab up my own rear suspension parts (I have a small stockpile of bits) and hang whatever suspension parts from the front that I want. It would make a good flat tracker, too (that is what the FT in VT500FT or FT500 was supposed to be for, anyhow.)
 

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Discussion Starter #9
In case anyone cared, I got it for $6.50. Through a network of people from another board, it got delivered to my house free of charge. I like the ideas behind the Lockheed Lounge shown on the Hell For Leather site, so I may go that direction (definitely doing a Hossack fork.)
 

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one of the worst things honda did was saddle the ascot with shaft drive and all that extra weight. Keep it light, keep it sporty. BMW manages to build performance bikes with shaft drives so why not you.
 

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Discussion Starter #11
Which brings up another good point. Rear suspension. I may try to do a paralever style rear, but maybe not at first. It may be a simple concept, but it requires some very precise machining to pull it off. For now, I have a few ideas, but if I happen to stumble upon a K-bike paralever arm cheap (yeah, right) I'll try to make that work.
 

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The first Yamaha Viragos were a monoshock shaft drive as was the Vision. Take a look at them for some ideas, too. In addition to the Hassock front end, you might want to consider a modern version of a girder front end. I would really like to look at one of those with a modern shock and good lateral bracing.

Ken
 

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Discussion Starter #13
The Hossack fork is better than a girder because you don't steer the suspension arms or the shock, which makes for lighter steering. Another advantage is that you can use longer supension arms which offer better geometry. Also, progressive rate linkages are possible with a Hossack fork.
I have seen the monoshock Virago setup (clean design) but I was thinking along different lines.
 

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I understand the advantages of the Hassock. The main objection, as I see it, is that it is big and ugly. I think a well done girder would look better and function as well for most uses. Done right would require the use of Heim joints and a well thought out geometry.
If the yamaha design is not what you are looking for, how about the Kawasaki design on the Ninja 650? Double sided swing arm, with a single offset shock without a linkage?

Ken
 

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Discussion Starter #15
I'll have to scan the pic of one of the original Hossack fork designs (from the Tony Foale book.) It wasn't big or ugly and actually looked quite a bit like a girder fork from a Vincent. I'll get back with that one. I do like the 650 rear setup, but mainly what I wanted to try was something that would reduce shaft torque reaction like a BMW or even an old Guzzi, where there are two pivots on the driveshaft and the final drive input remains parallel to the ground. Another pic I should scan while I am busy violating people's copyrights.
 

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Discussion Starter #17
I bet I'll never find one of those for $6.50!
 

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Discussion Starter #19
Not as in he is stupid, but as in "that stupid book makes me want to take on building a bike from scratch around a cheap motor, and now I need to buy the other one and the software."
 

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I understood what you mean.
I borrowed the book from a friend but luckily, he made me give it back
:D
PJ
 
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