GT240 Build

[Scooterdude]

its not quite that black and white though Dan,
I too use dyno's, gather the data, analyse that data, repeatedly test....As well as do the testing in the real world doing enough miles in differing conditions to be able to cross reference the dyno data to the real world data. Over the last 4 years all this has been on GT kits, including input towards its development. which lets be honest, GT is the back bone of this topic.

So what pipe would you recommend with this kit? I've heard good reports about the TSR Evo and in perticular the DT modified version, I think the plan is you tell him your set up and port timings etc and he makes it to suit.

[eden]

I would recommend the Fran race.
One of my customers now has a TSR on his after his Fran race wore out but he wishes he had bought another Fran race because his doesn't perform as well as it did on the road.
Having said that, he hasn't done that many miles in it yet, he is riding with us to Venice next week though so we will get a better idea during the trip.

[GeorgeS]

Got a carb setting question I'd be interested in hearing opinions & experiences on.

With the Fran Race my GT240 got a bit 'stuttery' between 4,000 - 5,000 rpm, I think this is a bit of a flat spot on the pipe before the kicks in around 6,000rpm (it wasn't apparent on a borrowed JL3). I've dropped the needle by one clip & it's much better, almost completely cured & rides very nice, maybe just the odd hint of a splutter hear-and-there.

The question is, I'm now on the top clip on the needle. Is it better to reduce the main jet & run a lower clip setting?

Carb (30mm PHBH) is set as:
145 Main (next step down is 142)
40 Slide
X13 Needle
70 Choke
AV268 atomiser
55 idle jet

Thanks,
George

[Rich_T]

I wouldn't be changing the main if it is fine on WOT. If the stutter is at a partial throttle opening and dropping the needle helps then I would suggest changing the needle to one with a different profile. For this you'll need to know the needle profiles and approximately what portion of throttle opening you're having trouble with. Personally, however, if you have almost cured it by dropping he needle all the way I would leave it at that for two reasons 1. needles are expensive 2. you're not going to be changing your jetting every day so don't make a snap decision based on one day, ride it for a few months first to be certain you're making a qualified decision.

[GeorgeS]

Thanks Rich, I'll get some more miles on it. It rides great, fantastic kit!

I will book a dyno session at Shiny Red Tuning in the coming weeks, I'll post up the results & any changes made.

[GeorgeS]

Image links edited from photobucket to IMGUR.

[eden]

Got a carb setting question I'd be interested in hearing opinions & experiences on.

With the Fran Race my GT240 got a bit 'stuttery' between 4,000 - 5,000 rpm, I think this is a bit of a flat spot on the pipe before the kicks in around 6,000rpm (it wasn't apparent on a borrowed JL3). I've dropped the needle by one clip & it's much better, almost completely cured & rides very nice, maybe just the odd hint of a splutter hear-and-there.

The question is, I'm now on the top clip on the needle. Is it better to reduce the main jet & run a lower clip setting?

Carb (30mm PHBH) is set as:
145 Main (next step down is 142)
40 Slide
X13 Needle
70 Choke
AV268 atomiser
55 idle jet

Thanks,
George

45 slide will help but make sure you go back to the settings you had before you try it.
I've tested this with two carbs set the same except for the slide.

[compass]

Apologies for jumping in..
I also have a very spluttery GT200 at 4000 -5000rpm (not a 240), which is making riding not fun.
Its always had a rich spot at those revs, but was always easy to rev past, however in the past year the range seems to be getting larger that I need to rev out/through to clear ?


running above with following..
130 main
55 pilot
AV 268
X13 on lowest

with a bgm clubman, augusto 6000, and a filter (have tried without filter and little difference)

Any suggestions on what to change next...Needle first?
Did wonder if running without the augusto would make much difference?


cheers

Compass

[HxPaul]

Apologies for jumping in..
I also have a very spluttery GT200 at 4000 -5000rpm (not a 240), which is making riding not fun.
Its always had a rich spot at those revs, but was always easy to rev past, however in the past year the range seems to be getting larger that I need to rev out/through to clear ?


running above with following..
130 main
55 pilot
AV 268
X13 on lowest

with a bgm clubman, augusto 6000, and a filter (have tried without filter and little difference)

Any suggestions on what to change next...Needle first?
Did wonder if running without the augusto would make much difference?


cheers

Compass

I dont know anything about jets,but I do know that the needle is on the richest setting.

[compass]

Apologies for jumping in..
I also have a very spluttery GT200 at 4000 -5000rpm (not a 240), which is making riding not fun.
Its always had a rich spot at those revs, but was always easy to rev past, however in the past year the range seems to be getting larger that I need to rev out/through to clear ?


running above with following..
130 main
55 pilot
AV 268
X13 on lowest

with a bgm clubman, augusto 6000, and a filter (have tried without filter and little difference)

Any suggestions on what to change next...Needle first?
Did wonder if running without the augusto would make much difference?


cheers

Compass

I dont know anything about jets,but I do know that the needle is on the richest setting.

I mean its on the top clip.