Author Topic: GS500 Classic Trials Project  (Read 16463 times)

0 Members and 1 Guest are viewing this topic.

Offline Paul K

  • Club Members
  • Sr. Member
  • *
  • Posts: 419
  • Paul Khambatta
Re: GS500 Classic Trials Project
« Reply #75 on: April 04, 2020, 09:20:18 am »
Good to hear that about the Supertrapp technology on a racer.  One guy told me that the Supertrapp was old technology; mind you, he was selling me a Motad exhaust system.  Would that Ďother silencer bodyí be that aluminium billet that you bored out?

Not much been going on in the rebuild what with the lack of parts :(.  Iíve had to order stuff online for home delivery; things like engine oil, fuel hose, hose clamps, wet & dry paper, masking tape and paint.  Most of its due next week so mucked about with a few small things.

Got the tank to fit correctly.  The underside was sitting on the cylinder head cover, but that was soon solved with a bit of hammer work ;).  Checked the tank doesnít leak by putting some fuel in.  The petrol came out a horrible brown colour so the tank needs flushing ::).  Cleaned and adjusted the gear change.  Tightened up all the engine mounting bolts.  Made some stainless steel pivots for the foot pegs out of some socket head screws.




Side stand needs a tweak and chainguard still to be fabricated.



Ground clearance is more than adequate and the seated and riding positions are comfortable.  I can also get both feet (in shoes) flat on the floor :D

Roll on next week.

Offline Tim Kingham

  • Club Members
  • Full Member
  • *
  • Posts: 114
Re: GS500 Classic Trials Project
« Reply #76 on: April 04, 2020, 03:18:32 pm »
I put some back paint on my white mudguard on my DR as at night when standing on the rests the headlight reflected on the guard and stopped me seeing the section ground detail

Offline Paul K

  • Club Members
  • Sr. Member
  • *
  • Posts: 419
  • Paul Khambatta
Re: GS500 Classic Trials Project
« Reply #77 on: April 04, 2020, 06:41:09 pm »
I put some back paint on my white mudguard on my DR as at night when standing on the rests the headlight reflected on the guard and stopped me seeing the section ground detail
Thanks for sharing that :(

Offline Jason Potts

  • Club Members
  • Sr. Member
  • *
  • Posts: 349
Re: GS500 Classic Trials Project
« Reply #78 on: April 05, 2020, 09:24:30 am »
That's looking very nice now Paul. Would this be eligible for class F?

I read your email by the way, one thing that has always peaked my interest is three wheelers. Think we chatted about this at Tamworth once.

Could you do a bit of a write up on your 2cv powered one please. Or just thoughts on three wheels in general. Or thoughts on 2cv and mods required to get them trials ready.

Would love to know what mods George has done to his Rialto. I seem to recall you can use motorbike tyres on them too. Did you go down this route?

Cheers
Jason

Offline Tim Kingham

  • Club Members
  • Full Member
  • *
  • Posts: 114
Re: GS500 Classic Trials Project
« Reply #79 on: April 05, 2020, 12:59:53 pm »
That would be interesting, Ive done a Trial on many bikes a sidecar or two and a car so that just leaves.....

Offline Paul K

  • Club Members
  • Sr. Member
  • *
  • Posts: 419
  • Paul Khambatta
Re: GS500 Classic Trials Project
« Reply #80 on: April 05, 2020, 04:37:26 pm »
Could you do a bit of a write up on your 2cv powered one please. Or just thoughts on three wheels in general.
Err, only if you can do a write-up on your bike builds  ;D

I seem to recall you can use motorbike tyres on them too. Did you go down this route?
You can fit motorcycle tyres to a three-wheeler if you can find some the correct size.  The 2CV had 15 inch rims and there's no trials tyres available in that size  :(

Offline Jason Potts

  • Club Members
  • Sr. Member
  • *
  • Posts: 349
Re: GS500 Classic Trials Project
« Reply #81 on: April 05, 2020, 08:13:01 pm »
Sorry Paul,  don't have any bike projects.

Been working away from home for a couple of years now. Don't have any time at the moment for projects. When I do get home I'm on decorating duty as we are trying to get our house ready to sell. We are going to move to North Wales later this year so plenty of stress going on. This covid 19 isn't helping either. All I can do at the moment is read and dream about trials. Sorry


Offline Paul K

  • Club Members
  • Sr. Member
  • *
  • Posts: 419
  • Paul Khambatta
Re: GS500 Classic Trials Project
« Reply #82 on: April 12, 2020, 10:30:57 am »
Fuel hose, hose clamps and engine oil arrived so I fitted those and a new oil filter and the engine's ready to fire up.  I had to jump start from a car battery because the bike battery I have is shot, but the engine fired and ran first time ;D.  But and a big but, it was loud! :o  I took another baffle plate out of the Supertrapp silencer, but that didnít seem to make any difference so a different silencer is required :(.

I took a look at the original Nexus silencer that was with the engine and decided if I cut and shut the huge collector box I can rotate the silencer to fit.  Out comes the grinder to find itís not a collector box; itís a double skinned pipe.  In fact the inner pipe is a smaller bore than the header pipes.



That outer pipe is going to be cut out and Iíve got some 45 mm pipe on order to make a connection between the header pipes and the silencer.  It should be quieter then.

Offline Stephen Bailey

  • Administrator
  • Sr. Member
  • *****
  • Posts: 473
  • AKA: Ratty.
Re: GS500 Classic Trials Project
« Reply #83 on: April 14, 2020, 01:27:07 pm »
Possibly put in an aftermarket db Reducer? About £10 from eBay.
Posts by myself are personal posts and in no way are an official expression of the MCC. or the MCC Committee.

https://www.youtube.com/watch?v=6_3KP7X8RQ4

Offline Paul K

  • Club Members
  • Sr. Member
  • *
  • Posts: 419
  • Paul Khambatta
Re: GS500 Classic Trials Project
« Reply #84 on: April 14, 2020, 06:51:24 pm »
Possibly put in an aftermarket db Reducer? About £10 from eBay.
I'm not an expert on exhaust design, but I get the impression that those db killers restrict gas flow so power is reduced.  If I was just going to use the bike for green-laning and the like, it probably wouldn't matter, but when you take it on a ride out with some guys riding large capacity road bikes, you want at least to be not too far behind.  And safe overtakes are best done quickly; you want to be in the opposite carriageway for as short a time as possible.

david@whitepost.me.uk

  • Guest
Re: GS500 Classic Trials Project
« Reply #85 on: April 15, 2020, 10:13:04 am »
On my bike I have an extension pipe with a DB killer on it for when I do the trials.

It makes a huge difference on the bike performance so it comes off if I'm not doing the trials.  :)

Offline Stephen Bailey

  • Administrator
  • Sr. Member
  • *****
  • Posts: 473
  • AKA: Ratty.
Re: GS500 Classic Trials Project
« Reply #86 on: April 16, 2020, 02:49:05 pm »
On my bike I have an extension pipe with a DB killer on it for when I do the trials.

It makes a huge difference on the bike performance so it comes off if I'm not doing the trials.  :)

 :)
Posts by myself are personal posts and in no way are an official expression of the MCC. or the MCC Committee.

https://www.youtube.com/watch?v=6_3KP7X8RQ4

Offline Paul K

  • Club Members
  • Sr. Member
  • *
  • Posts: 419
  • Paul Khambatta
Re: GS500 Classic Trials Project
« Reply #87 on: April 28, 2020, 07:35:22 am »
The 45 mm stainless steel pipe arrived so back to work with the grinder.  I cut a bit more of the outer pipe off the silencer to find that the inner pipe has a perforated section.  So what I thought was just a double skinned pipe looks more like an expansion chamber.  More welding, cutting, offering up, etc. and the Nexus silencer is fitted.


The bracket on the tube is the bump stop for the centre stand.

I temporarily supported the silencer with garden wire, started the engine and so much quieter and liveable with.  I shanít be upsetting the neighbours, or, more importantly, the scrutineer :).


The silencer is mounted far enough to the rear so I wonít burn my heel when the front on my boot is on the peg.

Now in the process of brush painting the tank, but my brush work is rubbish :(

Offline Jason Potts

  • Club Members
  • Sr. Member
  • *
  • Posts: 349
Re: GS500 Classic Trials Project
« Reply #88 on: April 28, 2020, 07:01:17 pm »
What kind of paint are you using Paul?

I've used enamel paint in he past and once fully dry I've wet and dried the heavy brush marks out and then t- cut it. Bit of work but it looked pretty good for a trials bike.

Offline Paul K

  • Club Members
  • Sr. Member
  • *
  • Posts: 419
  • Paul Khambatta
Re: GS500 Classic Trials Project
« Reply #89 on: April 29, 2020, 07:04:59 pm »
Iíve used Rustoleum Combicolor, the same paint as for the frame, just a darker blue.  The tank has had four coats so far ::).  The tank was rubbed down with 320 grit wet and dry, first coat of paint; flatted down with 800 grit paper; second of paint, looked a bit patchy; so third coat of paint, looked bl**dy awful with brush marks and dragging; flattened again with 800 grit paper; then final and fourth coat of paint.  The finish looks better, but itís no Rolls Royce.

I blame the quick drying paint, rubbish brushes and rubbish painter.  But thatís it.  I might try your technique of flatting down, but with a 1500 grit paper, then T-cut.  But I might not ;D.