Author Topic: GB Zorst  (Read 1048 times)

manxie

  • Posts: 1172
Re: GB Zorst
« Reply #15 on: July 03, 2016, 07:51:35 PM »
Cheers Steve, it is a good idea coz it`s probably worth a few quid but knowing my luck if I sold it ... I`d end up looking for one  :-\  ;D ;D
1980 Yamaha XT250
1985 Honda ATC200
1998 1200 Bandit
1978 Bultaco Sherpa project (not started)
1968 Kawasaki F3 175 Bushwhacker (project in progress)

manxie

  • Posts: 1172
Re: GB Zorst
« Reply #16 on: July 05, 2016, 06:38:52 AM »
It`s made of 304 stainless
1980 Yamaha XT250
1985 Honda ATC200
1998 1200 Bandit
1978 Bultaco Sherpa project (not started)
1968 Kawasaki F3 175 Bushwhacker (project in progress)

Moto63

  • Full Member
  • ***
  • Posts: 4051
Re: GB Zorst
« Reply #17 on: July 05, 2016, 09:38:10 AM »
Morning Steve, I'm certainly no expert but 304 stainless is pretty much the most common stainless used for zorsts etc. it's wot was used to do the one on my cafe racer although not thin walled so defo not the lightest system. I'm sure given the fact that you'd lose the collector box from the original system and obviously the silencer the stainless one would almost defo save you some weight. Plus (IMVHO) it looks nicer too. Keep us posted and like I say if you want me to send on the photo of the thin walled jobbie give me a shout
Cheers, Michael

manxie

  • Posts: 1172
Re: GB Zorst
« Reply #18 on: July 05, 2016, 10:24:09 AM »
Thanks Michael. I like the look of it too (and the sound  :) ) Do you think there`s need for re-jetting? Jack Batson recommends it. I`d rather not start messing with the carb?  :-\
1980 Yamaha XT250
1985 Honda ATC200
1998 1200 Bandit
1978 Bultaco Sherpa project (not started)
1968 Kawasaki F3 175 Bushwhacker (project in progress)

SteveC#222

  • Posts: 1900
Re: GB Zorst
« Reply #19 on: July 05, 2016, 10:35:44 AM »
Thanks Michael. I like the look of it too (and the sound  :) ) Do you think there`s need for re-jetting? Jack Batson recommends it. I`d rather not start messing with the carb?  :-\

It will probably need rejetting as it will be freer flowing. Usually a bigger main jet maybe moving the needle. Is it a CV carb like the XBR?  If you can get access to a Dyno it would be worth it. Can Jack Batson advise?
Growing old is inevitable, growing up is optional!

manxie

  • Posts: 1172
Re: GB Zorst
« Reply #20 on: July 05, 2016, 10:41:44 AM »
Hi Steve. I must be honest, I`ve not asked JB if it IS necessary, but he did recommend it. Not sure if the carb is the same as the XBR, I`ll take a look at it later. Cheers  ;)
1980 Yamaha XT250
1985 Honda ATC200
1998 1200 Bandit
1978 Bultaco Sherpa project (not started)
1968 Kawasaki F3 175 Bushwhacker (project in progress)

SteveC#222

  • Posts: 1900
Re: GB Zorst
« Reply #21 on: July 05, 2016, 01:57:29 PM »
Steve, this is the guy who's bike was in the Practical sportbike article I was telling you about I think he's from Yorkshire(?). I know he rejetted his GB so if you message him through Youtube he can probably tell you which jets you need.

Growing old is inevitable, growing up is optional!

manxie

  • Posts: 1172
Re: GB Zorst
« Reply #22 on: July 05, 2016, 03:56:45 PM »
Cheers Steve. I asked the question what would happen if I didn`t re-jet the carb, here`s the answer ........

The bikes are jetted very lean and I noticed that especially when riding at freeway speeds. I didn't want to pay the $80 for the jet kit so I tried installing a mainjet and I like jet and shimming the slide needle up. It was slightly better but I could eliminate the mid-range surge by pulling the choke on which wasn't acceptable so I went ahead and order the jet kit from Factory Pro just get the darn slide needle and all was better.

I`m not clued up with this sort of thing and don`t like messing about, all I`m looking for is to put a system on the bike, no hassle, something that looks nice and sounds nice to preserve the original??
1980 Yamaha XT250
1985 Honda ATC200
1998 1200 Bandit
1978 Bultaco Sherpa project (not started)
1968 Kawasaki F3 175 Bushwhacker (project in progress)

Moto63

  • Full Member
  • ***
  • Posts: 4051
Re: GB Zorst
« Reply #23 on: July 05, 2016, 04:41:51 PM »

[/quote]

It will probably need rejetting as it will be freer flowing. Usually a bigger main jet maybe moving the needle. Is it a CV carb like the XBR?  If you can get access to a Dyno it would be worth it. Can Jack Batson advise?
[/quote]
Evening Steve, yes I'd probably agree steveC  on this one, however I'd just check that the American GB was jetted to the same spec as the one you've bought. I know that generally the American spec bikes were jetted to run very lean to pass their emissions tests even back in the seventies they were generally different to what we got over in blighty. Best thing is to pop the system on and try it first, then take it from there. I'm sure even given the bit of hassle you'd have sorting out any rejetting it would be worth it in the end. You'd have a cracking looking and sounding system on your bike plus the original can be mothballed or sold on. Win. Win....best o luck and defo keep us all posted on it.
Cheers, Michael

manxie

  • Posts: 1172
Re: GB Zorst
« Reply #24 on: July 05, 2016, 05:02:13 PM »
Cheers Michael, yeah mine`s a US bike, also confirmed by Tony C when he called round for a cuppa TT week. I`m still chasing these bloody moths around the living room at the moment so...we`ll see?  ;)
1980 Yamaha XT250
1985 Honda ATC200
1998 1200 Bandit
1978 Bultaco Sherpa project (not started)
1968 Kawasaki F3 175 Bushwhacker (project in progress)

Moto63

  • Full Member
  • ***
  • Posts: 4051
Re: GB Zorst
« Reply #25 on: July 05, 2016, 05:28:24 PM »
Gooo ooonn you know you want one ;) ;)......it's what ya work for!!!.... Well that n payin the mortgage, gas bill, lecci bill and any other bill you can think of.
Goo oonn...you can always show the wife this post and blame it all on me ::) ::)