Motorbike I built………….

[Kenneth DeightonParticipant @kennethdeighton43272]

Hi, a beautifull machine. Yorkshire is a big place, where are you based ? so I can look out for you.

[littlerickParticipant @littlerick]

Wow….. You wanna come and play with my Ninja! Love it or hate it, that is one incredible acheivment of a machine… I love it.

I have trouble with a brake service!

[John Stevenson 1Participant @johnstevenson1]

Posted by ronan walsh on 06/10/2013 00:16:12:

That bike looks great shaun, its a credit to you. I sort of agree with you shaun, too many people in the worlds of home engineering and old bikes (the only hobby's i am interested in) are the sort you would run a mile from in real life, the anally retentative know all types – "oooh , your magneto lead clip is nickle plated when they were chrome plated for 1956" type bores.

For this reason i keep my distance from clubs and certain websites. This one isn't too bad.

.

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I can certainly relate to this or could in a previous life when I was actively involved with vintage racing bikes and you came across the eligibility committee.

Could be long, go get a coffee, and sorry for the hi-jack.

Something I found out early on was these 'ex – perts ' could never say " I don't know " they always had an answer but that is also their Achilles heel.and by applying pressure you could get them to agree with you as their only way out.

Once they say they don't know it opens the flood gates for someone who does, or thinks they do.

Friend of mine who used to do vintage racing like many had sheds full of bits. One day he asked me if I could shoehorn a Rudge engine into a Cotton frame, I replied more than likely but would need to see it first. He said he wasn't too certain whether to go ahead as Cotton never fitted Rudge engines, only JAP and Blackburn's.

So we hatched a plan, we wrote to The Motor Cycle and said that we had found a Cotton with a Rudge 4 valve engine fitted and our enquires had come up blank. Could they shed any light on this please ?

Back came the reply " Cottons fitted 6 Rudge engines as a trial and we probably had one of those "

OK build it and provenance has now been proved.

Some while later, October 1982 to be precise I was recounting this to a close friend who was also into racing bikes and he was very sceptical of the story as the first guy had moved out of the area so no proof.

So I grabbed a pencil and sketched an engine out completely out of the blue with his help.

This is a scan of the original pencil sketch done much later obviously, no PC's in 82.

It was a double crank, two pistons in one bore two stroke and to compensate for no crankcase compression it had a conical supercharger fitted { Did I invent the screw compressor first ? ]

Then drew Brough on the timing cover and sent it off to Bob Curry at the Classic Motor Cycle to ask if he could shed light on it

Couple of weeks later got a reply.

In all fairness he never said it existed but pointed out some close similarities to other designs and ended with a query that a FW Stevenson worked for George Brough, any relation ?

The letter and picture was published in Classic Motor Cycle with contact details for anyone to get in touch.

Outcome was two people rang to say that they had owned this engine and one guy wrote to say he's worked on it with George Brough.

It was a good hoot.

[Involute CurveParticipant @involutecurve]

I fear this thread has gone way of topic, yep there are fools all over the place so lets leave them to it, so in an effort to get it back on track i.e. engineering in what ever scale , I seek advice from all on here, I am unsure if this question should be in this area if not please let me know or perhaps a moderator can move it……..

On the new project bike which I started a couple of months ago, I will need to cut both internal and external splines, these will be straight sided as opposed to involute form, the reason being I already have several of these external spline cutters, however for the internal splines I am planing to use a 6mm keyway broach, I need six splines on the shaft so I intend to make a cutter guide with two slots in order to index the cuts, has anyone experience of this method, the materials to be cut are external Steel en24T, I have a high speed steel cutters for this, internal will be cut into 7075 T6 Aluminium, the finished splines I want to be a light press fit.

I did think about creating an electrode and sparking them but I would like to try machining them first, as I think this will give a better finish.

thanks in advance

Shaun

[John Stevenson 1Participant @johnstevenson1]

Shawn,

Yes easily done go to ArcEuro's home page

http://www.arceurotrade.co.uk/default.aspx

Let the adverts scroll up and there is one for keyway broaches with a pdf file of how to do it.

 

Cut the internal ones first as these are set in stone by virtue of the cutter used, then do the external shaft and adjust depth of cut to get the right fit.

Edited By John Stevenson on 07/10/2013 12:39:34

[Involute CurveParticipant @involutecurve]

Thanks for the link John that's an excellent article and pretty much what I was thinking of, I read an article years ago probably in ME, and as far as I can remember it was a similar approach.
The cutters I have for the shaft are marked as 6 splines and also have depth of cut engraved on them, in addition to the straight sided splines they also create during the cutting process the rounded shaft in the base of the splines, so I think the method as you suggested will be to turn the shafts outer diameter and then cut the splines to a depth that creates male splines measuring 6.025 across the flats, then mic up the shaft at the base of the splines and bore the boss an interference fit and also make a broaching button with two slots, then broach the slots to depth in two passes, sound easy I will let you know how it goes, although I wont be at this stage for a month or so.

Cheers

Shaun

[JasonBModerator @jasonb]

You might also want to take a look at teh last few pages of this thread, Andrew has been cutting similar splines and mating keyways. I've only done multiple keyways by indexing and slotting see this, not had the need since I bought some broaches but the method in JS's link would be a lot quicker.

J

[Involute CurveParticipant @involutecurve]

Excellent workmanship on both links, thank's

Shaun

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