Twinshock bike build.

[yorkshireracer]

thanks guys. I really appreciate all the help and feedback.

[Julz]

The later model twinshock bikes mostly seemed to go for angled rear shocks.
Modern damping technology and progressive spring rates may make this less necessary.
I've been told that you get what you pay for in trials bike shocks and that most serious people go for quality, rebuildable items, like
Falcon http://www.falconshockabsorbers.co.uk/trials-pg01.htm,
Rock Shocks http://www.rockshocks.co.uk/, or
NJB http://www.njbshocks.co.uk/.

Rock Shocks will supply any component part for any of their shocks if you damage one.

[Jon V8]

The later model twinshock bikes mostly seemed to go for angled rear shocks.
Modern damping technology and progressive spring rates may make this less necessary.
I've been told that you get what you pay for in trials bike shocks and that most serious people go for quality, rebuildable items, like
Falcon http://www.falconshockabsorbers.co.uk/trials-pg01.htm,
Rock Shocks http://www.rockshocks.co.uk/, or
NJB http://www.njbshocks.co.uk/.

Rock Shocks will supply any component part for any of their shocks if you damage one.

All of the above are well liked here in the UK.I had a ride out on my HT5 Ariel yesterday,first time in nearly a year.(Been waiting for a new wide ratio gear set to be made) It has new Falcons on the back,I'd forgotten how good they are,but now with the new clutch and gears sorted I want to sort the steering.Jacking the back of the bike up to sharpen the head angle is the first port of call.I mention this because the Falcons can be made shorter or longer with different ends,I dont know if the others do this,but it also means you can easily adapt them for a different bike etc.

[yorkshireracer]

I'll have a look at all those.
Classic trials here is pre - 65, pre-74 and air cooled drum brake which I think covers 74 to 82 so what to build ? As I understand, modifications aren't in the spirit of things but replica stuff is allowed.
I'm using 1980 engine and front end, so do I logically go with the more modern air cooled drum brake class or build an earlier frame and run in say pre 74. I'll probably (will have to check) get away with that unless I was winning or finishing well up that class (this is not a likely outcome ) in which case I'd probably get bumped up to the newer class any way.this is purely a personal preferance thing as I just prefer the earlier bikes.
Other option is an earlier frame but with the later geometry.
I'm looking at this as purely a fun recreational thing so (at least at this stage) not looking at anything ultra competitive.
If I go down early frame and later mods route and get bumped up a class, once i'd sobered up i can just build a more competitive bike and use the old frame for something else. I always have projects on the go and it would all be a learning curve anyway.

[yorkshireracer]

More thoughts on the frame debate Seeing as i'm using a Suzi engine, it seemed logical to use a Suzi frame which obviously means a Beamish.
Any thoughts ?
I've e-mailed owners club for a bit of info so see what happens.

[David Lahey]

being 1980 TS250, isn't your motor a centre-port exhaust? Beamish frames are single front downtube. If it is a side-port TS250 motor, I've seen people fit them into Sherpa T frames and look pretty good

[yorkshireracer]

thanks Dave. I would have spotted that eventually . told you i was new to this trials lark
Plan at this stage is to get something together at a (relatively) small budget just to get me out there, more do less talk. Once I' ve got this up and running then I' ll look at all the options for building for Oz.

[yorkshireracer]

Got reply back from Beamish o/c. Non of the original jigs, drawings have survived. Another case of throwing the baby out with the bath water !
He' s put me in touch with a guy in NZ who as a Beamish (and, it turns out lives in the same town) who also knows someone etc.
So, even if I use another frame for my bike I may still be able to do something with the Beamish at a later date.

[Julz]

I see from a comment you posted on the Trentham Summer Carnival post that you are in Wellington. If so, I can put you in touch with Alasdair from our group who has a Beamish Suzuki that you can take measurements from.

I would also be keen for you to take comparative measurements of my KT250 to see how they compare...

I'd be keen to know if the period tweak of cutting and extending the top tube (by about 20mm) will make the steering more like a modern bike. They say that both a Suzuki RL and a Kawasaki KT turn OK, but that you need to get over the front wheel to prevent them sledging out. I seem to have reduced this by adding Rox bar risers (to move my weight forward) but it would be interesting to know if the top tube extension (and resulting change to the fork angle) will have a similar effect. I know that Al's Beamish seems to turn better...

[yorkshireracer]

It was Alasdair that I got put in touch with. He sent me an e-mail and I just have to call him back. Feel free to give me a call 04 526 4205 and pop round sometime. Dave.