gt200 ?

[eden]

With box pipes 18-19 degrees. With expansions 17-18 depending on rev range.

Hey Rich, I'm quite surprised at the suggested 18/19 degrees on the box pipe.

Out of curiosity Rich, what's your personal reasoning on the differential between ignition timing on box pipes vs expansions? I'd be intrigued to know. Cheers, Dan.

RPM

[drunkmunkey6969]

With box pipes 18-19 degrees. With expansions 17-18 depending on rev range.

Hey Rich, I'm quite surprised at the suggested 18/19 degrees on the box pipe.

Out of curiosity Rich, what's your personal reasoning on the differential between ignition timing on box pipes vs expansions? I'd be intrigued to know. Cheers, Dan.

RPM

Thought I'd ask Rich, as he designed the kit and made the ign timing suggestions, but as you've replied and suggested it's down to RPM...

How does that equate on an ADS touring expansion pipe which peaks at 6500rpm and stonewalls, with no over-rev (and clears gasses quite effectively) vs a clubman (which quite often has trouble dissipating heat and clearing gasses effectively) but has substantial over-rev?

I'd have thought a static 16/17 would be a safer bet all round. Don't you agree?

Just my thoughts of course....

[steve chapman]

Ticks over ok , first or second kit 1 base gasket then packed then another base gasket , no head gasket all sealed with threebond, gt head , new carb, all running in has been done around town ECT, using a n3c plug , at time of nip up I was doing 50 behind a van and just eased of the throttle , steve

[eden]

Hey Rich, I'm quite surprised at the suggested 18/19 degrees on the box pipe.

Out of curiosity Rich, what's your personal reasoning on the differential between ignition timing on box pipes vs expansions? I'd be intrigued to know. Cheers, Dan.

RPM

Thought I'd ask Rich, as he designed the kit and made the ign timing suggestions, but as you've replied and suggested it's down to RPM...

How does that equate on an ADS touring expansion pipe which peaks at 6500rpm and stonewalls, with no over-rev (and clears gasses quite effectively) vs a clubman (which quite often has trouble dissipating heat and clearing gasses effectively) but has substantial over-rev?

I'd have thought a static 16/17 would be a safer bet all round. Don't you agree?

Just my thoughts of course....

Depends what compromise your happy with when using static ignition, you could just say retard it way down to be safe and forget about making a bit more power at commonly used rpm ranges and having a more economical motor, This thread is GT specific, the GT 200 has quite low head compression so it can handle more advance than other kits.
Personally I use progressive programmed retardation all the way down to 12 degrees at 9500 rpm, I wouldn't retard anywhere near that far with a box pipe though. as you said they don't dissipate heat well so whats the point in pumping even more heat into one? There is no advantage regarding power with pumping extra heat in to a box pipe as there is with an expansion as the returning pulse is so lame relative to an expansion any increase in speed of the pulse would be negligible.

Don't you think?

[eden]

Ticks over ok , first or second kit 1 base gasket then packed then another base gasket , no head gasket all sealed with threebond, gt head , new carb, all running in has been done around town ECT, using a n3c plug , at time of nip up I was doing 50 behind a van and just eased of the throttle , steve

whats your air screw (fuel screw) at?

[Muppet]

RPM

Thought I'd ask Rich, as he designed the kit and made the ign timing suggestions, but as you've replied and suggested it's down to RPM...

How does that equate on an ADS touring expansion pipe which peaks at 6500rpm and stonewalls, with no over-rev (and clears gasses quite effectively) vs a clubman (which quite often has trouble dissipating heat and clearing gasses effectively) but has substantial over-rev?

I'd have thought a static 16/17 would be a safer bet all round. Don't you agree?

Just my thoughts of course....

Depends what compromise your happy with when using static ignition, you could just say retard it way down to be safe and forget about making a bit more power at commonly used rpm ranges and having a more economical motor, This thread is GT specific, the GT 200 has quite low head compression so it can handle more advance than other kits.
Personally I use progressive programmed retardation all the way down to 12 degrees at 9500 rpm, I wouldn't retard anywhere near that far with a box pipe though. as you said they don't dissipate heat well so whats the point in pumping even more heat into one? There is no advantage regarding power with pumping extra heat in to a box pipe as there is with an expansion as the returning pulse is so lame relative to an expansion any increase in speed of the pulse would be negligible.

Don't you think?

I were just thinking the same

[drunkmunkey6969]

RPM

Thought I'd ask Rich, as he designed the kit and made the ign timing suggestions, but as you've replied and suggested it's down to RPM...

How does that equate on an ADS touring expansion pipe which peaks at 6500rpm and stonewalls, with no over-rev (and clears gasses quite effectively) vs a clubman (which quite often has trouble dissipating heat and clearing gasses effectively) but has substantial over-rev?

I'd have thought a static 16/17 would be a safer bet all round. Don't you agree?

Just my thoughts of course....

Depends what compromise your happy with when using static ignition, you could just say retard it way down to be safe and forget about making a bit more power at commonly used rpm ranges and having a more economical motor, This thread is GT specific, the GT 200 has quite low head compression so it can handle more advance than other kits.
Personally I use progressive programmed retardation all the way down to 12 degrees at 9500 rpm, I wouldn't retard anywhere near that far with a box pipe though. as you said they don't dissipate heat well so whats the point in pumping even more heat into one? There is no advantage regarding power with pumping extra heat in to a box pipe as there is with an expansion as the returning pulse is so lame relative to an expansion any increase in speed of the pulse would be negligible.

Don't you think?

Doesn't really answer the question though does it.

Most scooter owners are not using programable ignitions. What you think about pulses and the speed of returning waves means nothing to the guy in the street wondering whether to set his ignition and 19 or 16 degrees.

So why differentiate between box pipes and clubmans, when the RPM rages between the two cannot be clarified nor compared like for like. 19 could make more heat on a hi-revving clubman, than 16 would on a low revving expansion.

My thought/feeling is, that it would be safer to recommend 16/17 for ALL pipes. That way, those who don't have extensive tech knowledge set up conservatively and run safely, whereas those who understand the tech can disregard the suggestion (at their own risk) and choose what pipe/carb/ign settings they deem best for their own purpose.

Is the answer you gave in your first post 'RPM' something Rich confirms, or just your opinion on the matter?

[eden]

I always speak my own mind.... maybe Rich will post his own thoughts on the mater

[steve chapman]

2 1/2 turns out

[Rich_T]

Ticks over ok , first or second kit 1 base gasket then packed then another base gasket , no head gasket all sealed with threebond, gt head , new carb, all running in has been done around town ECT, using a n3c plug , at time of nip up I was doing 50 behind a van and just eased of the throttle , steve

First off, keeping it to the original thread. Dan I'll PM you me thoughts later so we don't descend into he said she said handbags.

Hi Steve, I think you are over compressed (not personally). The crank is a 110 rod and 60 stroke when the original kit is 107 rod 58 stroke. This means you need 3mm on the base gasket to accommodate the rod length and 1mm on the head to cover the extra 1mm in TDC stroke. I think you need to add the 0.9mm copper head gasket then adjust the squish back to 1.2 - 1.5mm which may require an extra base gasket.

essentially, because the mixture is over compressed you are getting much more heat into the piston and this is what is burning off the brown carbon deposits.