anyone had an RB25 on a dyno?

[simon k]

if so can you post a graph?
cheers Simon

[Bilko]

Give Taffspeed a call. I know Ian's been doing dynos on standard and tuned RB250's.

Due to many calls he's been getting, ian is asking for people to call between 1 - 2.30 or after 5.30

[22/2]

This is mine, built by Ian at Taffspeed Last summer, no problems yet.

Have a read of this thread on the LCGB site: http://www.forums.ilambretta.com/viewto ... =16&t=8939

Richie

[Chutney Brownlove]

Give Taffspeed a call. I know Ian's been doing dynos on standard and tuned RB250's.

Due to many calls he's been getting, ian is asking for people to call between 1 - 2.30 or after 5.30

Lunchtime and after they've shut?

If you can get Ian to the phone it's sometimes difficult to get him off again. I once watched my Sunday dinner go cold while he explained two stroke theory to me.

[Bilko]

Give Taffspeed a call. I know Ian's been doing dynos on standard and tuned RB250's.

Due to many calls he's been getting, ian is asking for people to call between 1 - 2.30 or after 5.30

Lunchtime and after they've shut?

If you can get Ian to the phone it's sometimes difficult to get him off again. I once watched my Sunday dinner go cold while he explained two stroke theory to me.

Been there!

[simon k]

thanks for the reply's lads.
Richie what set up are you running and is the kit modified?
cheers Simon

[22/2]

Simon

I'll answer as best I can, but Ian can give you chapter and verse.

Franspeed JL4
34 mm flatslide Dell'orto
AF RB 60 stroke crank
Original AF lightened flywheel and stator
Straight GP 200 gearing
Readspeed 6 plate clutch.
244.3cc

The barrel is modified slightly as it was one of the proto type kits (marked A01), 6 port, machined in error (I believe) at the factory to use a 58 stroke crank.

Ian cleaned up the cases around the crank matched the transfers and adjusted some of the port timings (because of the 60mm stroke being used) and machined the head to allow for the stroke.

He has achieved the power with his port timing rather than high compression, when we built it there was some scaremongering about running temps on the 225 version so I insisted on playing safe, the JL4 (as you can see from the graph) produces the power quite low down, the carb because thats what AF recommmend and the Delly can be set up more accurately than a Mikuni (although I have run Mikuni's on TS1 with no problems).

I've had TS1's up to 29 BHP but this is something else, it's quite brutal with the power delivery but you grin, not every time you ride it but every time you open the throttle, I haven't covered huge milage, maybe 1500 or so. The other thing about it is it pulls in top - properly, it's almost like another 3rd.

There is a video clip on youtube somewhere at Santa Pod for the NSA 50th anniversary meeting.


Rich

Rich