E: Engine Comet Mongrel

[eglijim]

I had another look at that swing arm and it would require a lot of material to be removed to clear the chain. That photo was taken at an angle so doesn't indicate the extent of the surgery required. Quite possible to do, but I'm already having trouble keeping this project relatively simple. It is a nice compact design and other than chain alignment, couldn't be simpler to install. Anyway, I'm now committed to another route, so that one will go back on the shelf for (assuming there is) the next project. I looked at the photos you posted on the other thread. May I ask what wheelbase you end up with? I like the rear shock mount.

View attachment 20387

Will have to ask Bob to measure the WB as the rolling bike is in his workshop,will let you know. Pic of the proposed frame would be nice ? The shock mount was one of Glenn's designs to serve as the frame abutment and keep the same geometry as the donor. the engine plates are probably over engineered and tie the engine /gearbox in nicely without using the normal Comet rear bracket. Will post a couple of pics of Ian Hamilton's BEARS racer design that Glenn was trying to slightly replicate.

 

[bmetcalf]

Is that a stock frame?

This is a KZ 1000 monoshock frame that may work with some serious modifications. I still have all the tooling and fixtures so may be easier to start with a new one.
View attachment 20389

 

[Bill Thomas]

I would have thought it would be more easy to copy a "D" Frame, With extra strength bars because it's a Comet, Cheers Bill.

 

[eglijim]

I would have thought it would me more easy to copy a "D" Frame, With extra strength bars because it's a Comet, Cheers Bill.View attachment 20396

Glenn Cs Comet special was always known "in house" as the geriatric Comet but you have beaten us by installing a Zimmer frame !.

 

[Bill Thomas]

Vincents make too much noise, So I thought I would put an Electric Motor in it, Ready for the year 2040 !.Cheers Bill.

 

[litnman]

Is that a stock frame?

.They were built for endurance racing in the late 70s.

 

[eglijim]

Will have to ask Bob to measure the WB as the rolling bike is in his workshop,will let you know. Pic of the proposed frame would be nice ? The shock mount was one of Glenn's designs to serve as the frame abutment and keep the same geometry as the donor. the engine plates are probably over engineered and tie the engine /gearbox in nicely without using the normal Comet rear bracket. Will post a couple of pics of Ian Hamilton's BEARS racer design that Glenn was trying to slightly replicate.

Ignore the giant 17 A/H battery, its the one from my electric start road Egli, just there for wiring up and testing.

Will have to ask Bob to measure the WB as the rolling bike is in his workshop,will let you know. Pic of the proposed frame would be nice ? The shock mount was one of Glenn's designs to serve as the frame abutment and keep the same geometry as the donor. the engine plates are probably over engineered and tie the engine /gearbox in nicely without using the normal Comet rear bracket. Will post a couple of pics of Ian Hamilton's BEARS racer design that Glenn was trying to slightly replicate.

Bob as had a measure, the wheelbase of Glen's comet special is 55.5 inches.

 

[Cyborg]

Thanks to you and Bob. I was hoping to get the WB down close to that point and I could get quite close, depending on if I use progressive linkage. No doubt just a shock would be simpler and take up less space if configured like a Vincent RFM. It will likely end up that way as the hours are piling up. I know an ex Honda factory fellow, who left to start his own business selling/rebuilding suspension for MX and road race bikes. He has agreed to help illuminate the path and has quite a good sense of humour. Anyway, according to my bride, we're off to someplace warm...

 

[eglijim]

Thanks to you and Bob. I was hoping to get the WB down close to that point and I could get quite close, depending on if I use progressive linkage. No doubt just a shock would be simpler and take up less space if configured like a Vincent RFM. It will likely end up that way as the hours are piling up. I know an ex Honda factory fellow, who left to start his own business selling/rebuilding suspension for MX and road race bikes. He has agreed to help illuminate the path and has quite a good sense of humour. Anyway, according to my bride, we're off to someplace warm...

Enjoy, allegedly we are in for a short sharp cold spell as a spring treat on the East coast here.

 

[eglijim]

Thanks to you and Bob. I was hoping to get the WB down close to that point and I could get quite close, depending on if I use progressive linkage. No doubt just a shock would be simpler and take up less space if configured like a Vincent RFM. It will likely end up that way as the hours are piling up. I know an ex Honda factory fellow, who left to start his own business selling/rebuilding suspension for MX and road race bikes. He has agreed to help illuminate the path and has quite a good sense of humour. Anyway, according to my bride, we're off to someplace warm...

One point to bear in mind with this design is hat we have VERY limited front wheel clearance so will need to fabricate an exhaust pipe with a fairly tight bend beyond the stub and we are using the front engine /stand plates. A shallower head angle or different offset yokes would ease this issue but at the cost of a slightly longer WB.