classic motorcycle forum

show us the finished job.
It'll never happen.

You're on the wrong thread. I'll put it down to dementia. I guarantee the job will be finished. Parts one and two of a welding course will be finished this time next year. By that time the design process will have been finished leaving fabrication of parts, welding of assembly followed by machining of axes perpendicular to swing-arm axis, on a milling machine. Strip down bike and build up on modified frame, which is a spare frame bought for £50. The seller had convinced himself it was bent, I told him it wasn't, he insisted it was bent, I gave him £50.

Which is the biggest problem with forums to do with old bikes, way too many no-it-all-back-in-the-day-when-I-where-a-lad-they-dont-make-em-like-they-used-to-you-cant-tell-me-owt shite ad infinitum. 'Experts' typically doing virtually zero mileage yet know everything about everything.

So I've finally learnt my lesson and have decided forums are definitely not for me. I thought I was just being unlucky coming across this type of 'enthusiast' again and again.

Look out for a Commando with BMW (Hossack) forks in the classic mags. Or if you see the bike out and about e.g at the Manx, come and say hello. Aufwiedersehen!

....is not a problem for any one whose bike deviates from standard. E.g brakes, engines, frames, front forks. Why anyone would want to bother though........Anyway, www.BikeSure.co.uk also http://www.devittinsurance.com/blog/a-guide-to-motorcycle-modifications-part-four-up-front/ can cover them to name but two . Did make me wonder for a moment how owners of Tritons, Tribsa's, Norvin's etc had got their bikes insured for all these years but obviously it's not a problem. This subject came up on another thread when I mentioned a plan to customise my classic bike..........some of the elderly do tend to worry themselves a bit .

'Why bother'? was a question, not advice.  I'm bothering because the Hossack fork design gets rid of all the problems associated with telescopics. It'll make it a better bike to ride, faster into and through corners, smoother all round. First thing to go when I bought the bike was the appalling front brake (Why bother?) I've now got switch gear and handlebar controls inc. master cylinder off a Honda CBR600 - far better than the standard junk and cheaper.

Tetchy? Your the one who chimed in whingeing about people modifying their bikes. There's too many people like yourself on forums harping on about what they used to do - probably because now they do sweet F.A, apart from droning on about when they were droning up and down motorways doing a 1000 miles a week. I bought my bike to ride, and if, in my opinion things need changing then they get changed. Couldn't care less about the sanctimonious arses towing bikes to rallies and then criticising somebody who's ridden their bike there because they've got Japanese spark plugs or non-standard light bulb.

Get the picture? 

 

More on the reasoning of the duo-lever suspension choice over telescopics. I'm of the opinion that nature is the greatest engineer. Millions, if not billions of years in research and development which continues to this day. The Norman Hossack design uses natures designs. The human leg, for example, consists of load bearing members (bones) articulated joints (ankles, knees) and spring/damper units (muscles).

I cant think of any example in nature where a telescopic design has been used to provide load bearing with sprung damping.

Ian, thanks for the comments.

Totally agree with your points regarding redesign of the frame, but only in the steering head area to support the lower and upper wishbone - it's the duo-lever design not the paralever. http://ridermagazine.com/wp-content/uploads/2005/09/2006_BMW_K1200R_front_wheel_Frame1.jpg

At the moment the idea is to remove the steering head entirely. Before cutting I'll check the swinging-arm axis is perpendicular to the frame centre-line and correct if necessary. The swinging-arm axis will then be the datum to work from to establish the new mounting points for the wishbones are parallel to that.

I'm aware that tele's were originally fitted to Commando's but as long as the front wheel trail and wheel base is fairly close to the original I don't for see any problems, unless anybody knows better - I'd be grateful for any more input.