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A couple of short clips of the very first few miles on a new GT250 that I've just finished.

spec is:
GT200 bored to 71mm quite heavily ported
Wossner H2 piston moded
Porcupine head re-profiled
62/115 crank
LTH 7 plate clutch
Cyclone 5 speed box
Electrex ignition
Fran race exhaust

Video starts when the motor has under 8 miles on the clock, I give it full throttle once at 2:20 in the video in 3rd but don't let it rev all the way out as at this stage it only had 11 miles covered on the engine.

very very pleased so far

Jesus Christ
this is amazing.
If you have a port map,
I'm interested

what piston to bore clearance did you use ?

4 thou.

Sounds sweet as !! G.

Eden wrote:A couple of short clips of the very first few miles on a new GT250 that I've just finished.

spec is:
GT200 bored to 71mm quite heavily ported
Wossner H2 piston moded
Porcupine head re-profiled
62/115 crank
LTH 7 plate clutch
Cyclone 5 speed box
Electrex ignition
Fran race exhaust

Video starts when the motor has under 8 miles on the clock, I give it full throttle once at 2:20 in the video in 3rd but don't let it rev all the way out as at this stage it only had 11 miles covered on the engine.

very very pleased so far

fucking hell that's rapid

Looks good Eden.
Bit more info please mate
Is the crank one of Richards, is it welded, and is the small end 18 mm?
Is the normal kit designed to bolt on with a 107 mm rodded crank etc etc you know the info we want

How are you finding the 5 speed box
Is it one of the latest ones which I understand are stronger

soullad wrote:Looks good Eden.
Bit more info please mate
Is the crank one of Richards, is it welded, and is the small end 18 mm?
Is the normal kit designed to bolt on with a 107 mm rodded crank etc etc you know the info we want

no this crank is AF 60mm webs with eccentric pin making it 62 and RD 115 rod, not welded, I started this motor before Richards cranks were available, that said though, he is only doing 110 rods at the moment. I have Richards prototype 62/110 crank in what was my 230 making it now 240, just got it back together in my winter model tonight so will be running around on that soon.

the normal kit is designed for a standard crank yes although putting a 60 with 110 rod works too, Richard has had some base packers made for this application but obviously it would benefit from some small port changes to work better with the longer stroke and rod.

jonoy wrote:How are you finding the 5 speed box
Is it one of the latest ones which I understand are stronger

As far as I know its one of the stronger ones yes (the guy ive done the engine for supplied the box) and from the few miles ive done on it so far I'm already thinking 4.7 final drive maybe a bit too short for this motor with a 5 speed box as I have tended to ride it using 3rd where I would normally use 2nd on a 4 speed. In that video I'm in 3rd when I overtake that car.

TBH I need to get some miles on it so I can ride it normal before I will be able to tell. however, 4.7 gives about 11mph per 1000rpm so its long enough for normal touring speeds IMO as 7k rpm is over 76mph, my 250 that I did last winter will hit 8k rpm in 4th with 4.7 final drive and in all honesty thats more than as fast as I want to go on the road.

Hi Eden intrested on your thoughts on the electrex ignition is it easy to set up etc cheers Ian

ian i.o.w wrote:Hi Eden intrested on your thoughts on the electrex ignition is it easy to set up etc cheers Ian

easy enough to get the ignition sorted but the small regulator has 4 pins and no mention of which wire goes to which so I wired my wassel up to it.

See my oily rag info on the Electrex kit. It works great but the info out there & the customer service is sparse to say the least. there are plenty of unanswered questions .... Does the CDI contain the auto retard info. If so, where do you buy a spare? If only Electrex sorted this out, passed over some info & sold spares. Their silence smacks of paranoia.

soullad wrote:See my oily rag info on the Electrex kit. It works great but the info out there & the customer service is sparse to say the least. there are plenty of unanswered questions .... Does the CDI contain the auto retard info. If so, where do you buy a spare? If only Electrex sorted this out, passed over some info & sold spares. Their silence smacks of paranoia.

I fitted one to a mates engine a couple of months ago and we used his original CDI and it still retarded so from that I presume its in the pickup, however the one fitted to the 250 in the video above has the supplied CDI and it doesn't retard as much as the other one I fitted which is odd

Thanks for the reply Eden I know of people using one in other bikes and they rate them worries me a bit if they go wrong on rally always carry spare bgm stator and then can get home thanks again cheers Ian

You'd also need another flywheel and possibly CDI, both sets of tools etc etc

Finished running this in the other weekend.

Some uncut footage while on the Fossway traveling from Wollacombe to Cadwell
At this stage the motor had around 650 miles on it I think

taking it easy keeping it just under where the power kicks in hard at 6k rpm as it had to make 530 miles that day

Can I ask which gearbox oil you are using ?

standard ST90

Eden.
How is the fuel consumption with the 5 speed box? I believe this is a new addition too.
Cheers Shane.