Page 1 of 2
RB Exhaust Thoughts

Posted:
Mon Feb 20, 2023 12:41 pm
by Solid Air
I'm going to be building an RB270 soon, just waiting on the CasaCase so I can get started, and would be interested in what exhaust others are using with similar set-ups (not restricted to the RB). I have the option of having a pipe made but if there is an off the shelf item that would work well then that would obviously be easier.
I'll be using the following:
RB 225
The barrel will be cast iron sleeved with the necessary ali or packers added to the top and bottom
70mm piston
70 x 120 crank
AF Mammoth head
AF 5 speed
Mikuni 30mm TMX
Static ignition
Aiming for peak power to be around 6k revs, max 7k, tuned more for torque and touring rather than max HP
I'd be interested in your experiences and thoughts.
Thanks, Mark
Re: RB Exhaust Thoughts

Posted:
Mon Feb 20, 2023 9:25 pm
by Toddy
Mark might be worthwhile speaking to Scotty (Darren Scott) he has a bit of experience with RB motors

Re: RB Exhaust Thoughts

Posted:
Mon Feb 20, 2023 9:45 pm
by Solid Air
Good idea, cheers Paul
Re: RB Exhaust Thoughts

Posted:
Tue Feb 21, 2023 7:55 pm
by GRTDKAD
RB250, 30mm Dellorto VHSH, AF Mammoth, AF
62mm Race Crank 116mm rod
Front sprocket 20T, Crown Wheel 47T
AF Road 6 plate clutch, AF CLO5E 5-speed box
Tornado exhaust
Goes well, though I’ve had a few folk tell me that I shouldn’t have a tornado on there.
Re: RB Exhaust Thoughts

Posted:
Tue Feb 21, 2023 9:11 pm
by nastro azzurro
Why not the tornado?
I’ve had to put an old tourer on mine after the supertourer split beyond repair.
Supertourer was far better than the tourer and was considering a tornado but don’t know anyone using one…
Re: RB Exhaust Thoughts

Posted:
Wed Feb 22, 2023 1:33 pm
by Solid Air
GRTDKAD wrote:RB250, 30mm Dellorto VHSH, AF Mammoth, AF
62mm Race Crank 116mm rod
Front sprocket 20T, Crown Wheel 47T
AF Road 6 plate clutch, AF CLO5E 5-speed box
Tornado exhaust
I have read that that It is a higher revving exhaust, but if you're happy how it rides that's all that matters surely?
Goes well, though I’ve had a few folk tell me that I shouldn’t have a tornado on there.
Re: RB Exhaust Thoughts

Posted:
Wed Feb 22, 2023 1:35 pm
by Solid Air
Interested in the the Pipe Design Voyager RB Mk II, waiting on an email response from them
Re: RB Exhaust Thoughts

Posted:
Fri Feb 24, 2023 9:43 am
by GRTDKAD
nastro azzurro wrote:Why not the tornado?
I’ve had to put an old tourer on mine after the supertourer split beyond repair.
Supertourer was far better than the tourer and was considering a tornado but don’t know anyone using one…
I’m happy with it, may just be a case that everyone has an opinion. “Too peaky” iirc, but it rides well.
Re: RB Exhaust Thoughts

Posted:
Fri Feb 24, 2023 10:22 pm
by nastro azzurro
Thanks. Might give it a go.
Re: RB Exhaust Thoughts

Posted:
Sun Feb 26, 2023 10:00 pm
by Solid Air
Realised I might be missing a trick, I've got an Ex-Box ST not being used that could work very well with this set-up. Have ordered an RB manifold from Ron Moss and will see how it works when it gets built.
Re: RB Exhaust Thoughts

Posted:
Mon Feb 27, 2023 4:25 pm
by jonashford
super tourer
Re: RB Exhaust Thoughts

Posted:
Tue Feb 28, 2023 9:29 am
by Solid Air
Have had a Supertourer before but didn't get on with it sadly, up hills or into a headwind it would drop out of the power much too easily, hard work. Thanks though
Re: RB Exhaust Thoughts

Posted:
Tue Feb 28, 2023 2:40 pm
by hullygully
jonashford wrote:super tourer
great all round exhaust, on a TS1 though
Re: RB Exhaust Thoughts

Posted:
Mon Apr 10, 2023 11:27 pm
by Simon_T
hi
ive just bought a 30mm vhsh for my rb230 can I ask what your jetting is please.
regards
GRTDKAD wrote:RB250, 30mm Dellorto VHSH, AF Mammoth, AF
62mm Race Crank 116mm rod
Front sprocket 20T, Crown Wheel 47T
AF Road 6 plate clutch, AF CLO5E 5-speed box
Tornado exhaust
Goes well, though I’ve had a few folk tell me that I shouldn’t have a tornado on there.
Re: RB Exhaust Thoughts

Posted:
Wed Apr 12, 2023 3:07 pm
by GRTDKAD
Simon - the attached was the go-to spec from Ben at Rayspeed for the RB25 and VHSH30 set up.
*My carb was worn so more or less everything needed replacing!
Hope you’re not too far off:
DQ267 ATOMISER
30MM/ 34MM DELLORTO MAIN JET 170 SIZE 6MM
FLAT SLIDE FOR DELLORTO VHSH 30 VHSH NO. 40
U16 NEEDLE
DELLORTO NEEDLE CLIP
DELLORTO VHSH30 CHOKE JET 50
30MM/34MM DELLORTO PILOT JET 50 SIZE 5MM
30MM STEPPED CARB RUBBER
30MM DELLORTO TO TS1 / RB 40MM ID TO 35MM ID
Re: RB Exhaust Thoughts

Posted:
Wed Apr 12, 2023 5:53 pm
by Adam_Winstone
Are you intending to run it in a full frame? I ask as the long stroke and long rod do push the head forward by a considerable amount. I ended up looking to claw back every mm available with my 72 stroke 120mm rod, having to undo the legshields and runners to push them as far forward as the slots would allow.
Will the larger Mammoth head still fit? You may want to ask the question of clearance constraints with DT's big cc RB and Mammoth head (shorter stroke too).
Interesting project though

Re: RB Exhaust Thoughts

Posted:
Wed Apr 12, 2023 8:40 pm
by Solid Air
Yes Adam, the frame clearance is an issue that we have thought about. I'm hoping that RLC will be dispatching the casings any day now, then once the engine is all together we can see what we are dealing with. Appreciate your post though

Re: RB Exhaust Thoughts

Posted:
Wed Apr 12, 2023 9:28 pm
by Adam_Winstone
Yep, I did the same as there's nothing quite like assembling and checking out the reality of what hits where, influence of eccentric cones, etc.
I look forward to progress updates.
Re: RB Exhaust Thoughts

Posted:
Wed Apr 12, 2023 9:30 pm
by Solid Air
Thanks Adam, hopefully it won't be too long now.
Re: RB Exhaust Thoughts

Posted:
Mon Apr 24, 2023 9:04 pm
by Simon_T
GRTDKAD wrote:Simon - the attached was the go-to spec from Ben at Rayspeed for the RB25 and VHSH30 set up.
*My carb was worn so more or less everything needed replacing!
Hope you’re not too far off:
DQ267 ATOMISER
30MM/ 34MM DELLORTO MAIN JET 170 SIZE 6MM
FLAT SLIDE FOR DELLORTO VHSH 30 VHSH NO. 40
U16 NEEDLE
DELLORTO NEEDLE CLIP
DELLORTO VHSH30 CHOKE JET 50
30MM/34MM DELLORTO PILOT JET 50 SIZE 5MM
30MM STEPPED CARB RUBBER
30MM DELLORTO TO TS1 / RB 40MM ID TO 35MM ID
Thankyou