February 27, 201016 yr The John Reynolds bike 'looks' more standard cosmetically , but the swinarm is longer to compensate for the further forward swingarm pivot. As Woody says it does not have a swingarm spindle but two pivot points either side of the engine between the frame and cases. Edited February 27, 201016 yr by pedronicman
February 27, 201016 yr There was a later bike done for John Reynolds which had the pivot moved even further up. On this bike it looked as though the pivot went through the rear of the cases but the swingarm was actually bolted to the side plates either side so there was no spindle. Don't think there is any room in the cases to allow a pivot to pass through, without reworking the internals that is. The comerford bikes (reg mays conversions), John's and mine both have the cases machined/cut away which moves the pivot an extra 12mm or so.
February 27, 201016 yr The John Reynolds bike 'looks' more standard cosmetically , but the swinarm is longerto compensate for the further forward swingarm pivot. As Woody says it does not have a swingarm spindle but two pivot points either side of the engine between the frame and cases. This was the last JR bike which wasn't around that long if I remember correctly, he had a couple before, which were like vestys, definately.
February 27, 201016 yr The cases are hollowed away where the swinging armcentre bracet is shortened. It takes a bit of the web but doesn't touch the gearbox internally. Ah, ok - I missed that when I was crawling all over the bike a few years ago, looked like they were untouched - Apologies Tim, you were correct.
February 27, 201016 yr The Comerford (Reg May) 340's I think there were about 40 of them altered and sold for about Edited February 27, 201016 yr by Big John
February 27, 201016 yr Ah, ok - I missed that when I was crawling all over the bike a few years ago, looked like they were untouched - Apologies Tim, you were correct. No problem Woody. Dabster, I thought you sold yours?
February 28, 201016 yr No problem Woody.Dabster, I thought you sold yours? I have one bike complete left, the comefords one I sold to john moffat. However the one I have was supposed to be a john reynolds bike but Dave Renham checked the numbers and can't be 100% sure either way, although it was from up that way so could be a copy without the radical pivot. It has some other probable later mods too. Some if not all the comerfords bikes had whitlock swinging arms which were oval tube, i transferred that to my current bike. I know about the engine case cutting as reg may did my frame as a seperate thing having bought the bike from julian wigg motorcycles and ridden it for a while. I still have one untouched frame which would be a great donor for a super special frame chop, and I have always fancied the seperate pivot points as described by pedrionica above. Would imagine that the rear of the engine would still need supporting somehow. Dave Thorpe at the time questioned the purpose of the gain of moving the pivot point forward but i'm sure it was a benefit in more than a couple of ways. will try to post photos soon. Richard Allen had the bike in the photo i posted above, think he bought it from comerfords (?) and I got to ride it once in a trial in wales in the 90's ACU twinshock series (as was Falcon I think). Definately had longer shocks maybe 14.5". Pretty sure this is the same bike Bultaco uk are selling.
February 28, 201016 yr I know about the engine case cutting as reg may did my frame as a seperate thing having bought the bike from julian wigg motorcycles and ridden it for a while. I still have one untouched frame which would be a great donor for a super special frame chop, and I have always fancied the seperate pivot points as described by pedrionica above. Would imagine that the rear of the engine would still need supporting somehow. As far as I can work out there's two ways to do it, firstly as described above, take a nibble out of the back of the crankcases and use a standard s/arm pivot bolt OR use two stub axles that thread into mating blind threads welded to the rear engine mount. But this will not be very, structurally, sound. Hey Dabster you don't fancy throwing together of that twinshock Carlos Iso design do you? Somebody has to do it.
February 28, 201016 yr As far as I can work out there's two ways to do it, firstly as described above, take a nibble out of the back of the crankcases and use a standard s/arm pivot bolt OR use two stub axles that thread into mating blind threads welded to the rear engine mount. But this will not be very, structurally, sound.Hey Dabster you don't fancy throwing together of that twinshock Carlos Iso design do you? Somebody has to do it. One of Johns 340's has a hack out of the swinging arm boss and bush to make room, at least one I have pictures of does. On the Carlos Iso design, the thought had crossed my mind over this last week. His designs when you take them in context with the associated text are more a fictitious study of what could of been. So would be interesting to make at least one exist in one way or another. Wayne....
February 28, 201016 yr One of Johns 340's has a hack out of the swinging arm boss and bush to make room, at least one I have pictures of does.On the Carlos Iso design, the thought had crossed my mind over this last week. His designs when you take them in context with the associated text are more a fictitious study of what could of been. So would be interesting to make at least one exist in one way or another. Wayne.... Carlos was quite emphatic (well, as you can be when using Babelfish) that his design was what could have been. Had another thought about the stub axles. The design could be quite robust. By extending the rear engine mounting bracket to mate with the bash plate (ala Gas Gas) the arrangement would be much stronger.
February 28, 201016 yr I have one bike complete left, the comefords one I sold to john moffat. However the one I have was supposed to be a john reynolds bike but Actually Dabster, the bike you sold me had Reynolds stamped under the cylinder head! Richard Allen had the bike in the photo i posted above, think he bought it from comerfords (?) And... the bike I bought from you had R.Allen stamped on the cylinder head steady!!! Just an observation! Big John Edited February 28, 201016 yr by Big John
February 28, 201016 yr One of Johns 340's has a hack out of the swinging arm boss and bush to make room, at least one I have pictures of does.Wayne.... Yes you are completely correct Wayne it does indeed, that very swinging arm was in my sweaty hand this very evening! I was having a browse in the "Batcave" Big John
March 1, 201016 yr Carlos was quite emphatic (well, as you can be when using Babelfish) that his design was what could have been.Had another thought about the stub axles. The design could be quite robust. By extending the rear engine mounting bracket to mate with the bash plate (ala Gas Gas) the arrangement would be much stronger. Not so sure the late head steady was a development to stop the top tubes bending. The rear engine mount is important I'm sure.
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