V-Twins in Featherbeds

I saw this parked up at the top of Bray Hill last August - I love it !!

 
I like that too, but I would not try to race it. A while back one of our guys was racing a V-twin JAP in a featherbed frame - it was useless. It had a ton of torque but was totally unsuited to our tight local circuit. It doesn't matter how you gear it, it is impossible to ride fast. A triton is bad enough for weight distribution without all that extra mass towards the back.
Years ago in Victoria, Arthur Pimm had a 1000cc Vincent motor in a featherbed frame which won a lot of races against 500cc Manxes - mainly at Phillip Island which is a 'power circuit'. It was extremely fast down the long straights, but much slower around the corners. There is only one Phillip Island in Australia.
 
I would love to put a 1200 Evo Sportster motor into my Slimline Featherbed frame but the thought of hacking up a good frame to fit it in is not what I wish to do but the idea has been in my head for a long time.

Ashley
 
I would love to put a 1200 Evo Sportster motor with a nice 5 speed close box, into a MK3 Seeley frame. But for what purpose could you use it ? You could get it going and handling, but I don't think the BOTT race class still exists. As a road bike, it would be a pain.
 
With the engine shown in the photo above - you could get it two inches further forward in a MK3 Seeley frame. Might actually handle. There is a guy here who races a Panhead Harley motor in a featherbed frame with a Triumph gearbox. Seems to go OK. The bikie gang guys love it.

 
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I would love to put a 1200 Evo Sportster motor with a nice 5 speed close box, into a MK3 Seeley frame. But for what purpose could you use it ? You could get it going and handling, but I don't think the BOTT race class still exists. As a road bike, it would be a pain.

Well for one thing there is more to building and riding motorcycles than just for the track and a 1200 Evo Sportster in Featherbed frame would be unique and done right would be a pleasure to ride ON THE ROAD.

Ashley
 
I agree Ash, and there’s no shortage of donor motors either. I’m kinda surprised there’s not more of ‘em really.
 
I agree Ash, and there’s no shortage of donor motors either. I’m kinda surprised there’s not more of ‘em really.

There have been many Shovalhead Sportster motors in Featherbed fames but the problem with the Evo Sportster motor is the frame rails have to be cut etc for it to fit and it be ashame to cut up a perfectly good orginal Featherbed frame, I have looked into it and had a donor motor to messure up but won't fit unless there is cutting and I won't do that, but a alloy EVO Sportster motor would be a good combination, I throught about a replica Featherbed frame but to me they are not a true Featherbed in my eyes.

Ashley
 
If you use a replica featherbed frame, it can be a Manx copy. The Slimeline frame is pretty naff. But for a Sportster motor, a Mk3 Seeley frame would be a much easier build. The front head would not have anything to hit when you kept the motor forward. The thing about the Featherbed is the weight distribution. If the weight is not well forward, the bike can feel light and scary in high speed corners. With a heavy motor, that is not good - destroys confidence. One of our local guys is involved with racing a Norvin - told me the weight distribution is 50% - I would not like to race that. It is too big and if it got light in corners, it would feel really bad. When it is raced, it is always point and squirt - no fast cornering.
 
I would love to put a 1200 Evo Sportster motor into my Slimline Featherbed frame but the thought of hacking up a good frame to fit it in is not what I wish to do but the idea has been in my head for a long time. Ashley

Suggest you look at the frame makers of new f/b frames one or two will make a frame for a Harley if you really want to do it ;)
 
My problem is I have my 850 Wideline F/B thats a goer and a Slimline F/B project bike that only has the front end and rear end together sitting waiting for me to put it together, it wouldn't be hard to put a different motor into it if it fitted without hacking into the frame, but spending money on a replica frame made to fit the Evo motor then its not a true F/B frame in my eyes I only have a love of true orginal Featherbed frames, my Wideline is a 57 and my Slimeline is a 60s Manxman and just spending my hard urned cash on a new 1200 Thruxton which I got to say rides and handles as good as a well set up Featherbed, but its good having these ideas running through my head as now no longer working I have the time to do more things when not out on the bikes.

Ashley
 
I also think a Wideline be better for a Evo motor to fit in the frame compared to a Slimline.

Ashley
 
I also think a Wideline be better for a Evo motor to fit in the frame compared to a Slimline. Ashley
Wideline /Slimline they will make either as regards originality - you resole your shoes to avoid buying new ones,but they then are nor original anymore!
If you have to cut the engine or original frame to fit it would be better to obtain a custom built new frame in the first place so that you can say no Norton frames were hurt in building this bike!;)
 
Only to be rich to afford to do these things, I am only a poor old pensioner with to much time to spare , well not really have to many bikes to ride and not enough time to ride them all lol.

Ashley
 
It is surprising how quickly a project can come together, if you work steadily towards it. You don't need to pay top dollar for everything if you are patient. I've built several race bikes from the ground up. When I built the Seeley, I had to find out where the rolling chassis had gone. When I found it, it was corroded but usable and did not cost very much. If you go to race meetings and get to know the guys, often they have stuff they are willing to sell at reasonable prices. There is one thing to remember however - it is easy to build a bike which will scare you shitless.
 
Fully agree with you Al, when I first started to built my 850 Featherbed in 1980 I wasn't working and lived on the dole so used as much as I could from the Commando that I could and the parts that I had for the Featherbed frame, mixing both to make it work, most money went to the motor rebuild, crank balancing, cam grind, reboar, and head work and a few months work here and there in between, but what I done worked so well I had such a well balanced hot Featherbed and only the last 10 years I spent money to upgrade things to make it even better.

Ashley
 
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