My scooter seems to have slowed down

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camel
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a.j wrote:Yeah piston is drilled to suit ..
drilled? :roll:
have you done a boost port?
ive just built a spare motor and currently got it in my bike to dial in,it too is an iron sr 66.5 piston,mb reed block and a 28 dellorto.
what carb settings have you got in?
im currently on
300 fuel valve
av264 atom/x13 needle on second clip and a 125 main
40 slide/70 choke
im currently on an af clubman and it feels strangled if im honest but i havnt got any miles on it yet
a.j
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I will let you know weekend mate...All I can say is that without the kegra, agusto & reed block it went fine..
camel
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strobe ignition to rev out to 16 degrees
if in doubt bypass the agusto and static time to 16-18 degrees
set up the carb to something like ive mentioned
if no joy id eliminate the pipe..is it new?or is it coked up?...change to whatever you ran before..
if still no joy id suspect the "tuning" of the barrel/piston
thats how i would attack it.
good luck



your brake isnt over adjusted is it???lol
a.j
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I am going to take the kegra off and put the af reverse cone back on this morning. See how that goes..
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Andy Pickering
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ove wrote:Eaten too much over Christmas!!!!
After reading all the answers id still go with that lol bet jeans have shrunk as well ;-)

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Ricspeed, gone but never forgotten RIP my friend #59
a.j
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Update. Tried 2 different exhausts, no difference & the kegra pipe remains. Took the agusto off, it seemed to improve. Removed air filter & seemed to improve, but I will not run it normally without a filter & purchased a remote marchald which has yet to be fitted. Have kept the reed block on. On the dyno it read 76 mph. But I went up a steep hill yesterday into a very strong headwind & I was cringing as I crawled up it in 4th (sx200 gearbox) before change down. On the flat I opened the throttle to the hilt & noticed a drop off in revs & it picked up again when I turned the power down a touch. The weather has stopped me going out today with my garmin speedo attached to get some idea of loss of power on the road. I want to compare my scooter to another bike now as it's been a while since I rode my lambretta, I'm thinking that maybe being on the GTS for work & everything else through the winter has tuned my brain into thinking my Lambretta is under performing & until compare it to another I'll have no idea.

It is frustrating when you buy things to increase performance & over £300 spent for no noticeable improvement.
Adam_Winstone
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Sounds like it is overgeared then. Don't forget that tuned engines with bigger carbs and free flowing exhausts tend to make their additional power at higher revs. Long gearing often works in the opposite direction to motors that want to make power at high revs, hence AF recommending that people dropped from 4.8 to 5.2 when using revvy pipes on their 20BHP TS1 kits. BHP does not = the ability to pull long gearing, rather it is all about where in the rev range that power kicks in.

With a Kegra pipe on, you could find yourself in the realms of needing the motor to keep revving hard to keep making the power, let the revs drop and you drop out of the power too. If this is the case then you can't cruise at low revs in 4th but it'll go like a rocket at higher revs in 3rd. The way to get it to go like a rocket in 4th is to bring the gearing back and let the motor reach the powerband easier... and stay in it.

Adam
Grumpy225
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a.j wrote:Update. Tried 2 different exhausts, no difference & the kegra pipe remains. Took the agusto off, it seemed to improve. Removed air filter & seemed to improve, but I will not run it normally without a filter & purchased a remote marchald which has yet to be fitted. Have kept the reed block on. On the dyno it read 76 mph. But I went up a steep hill yesterday into a very strong headwind & I was cringing as I crawled up it in 4th (sx200 gearbox) before change down. On the flat I opened the throttle to the hilt & noticed a drop off in revs & it picked up again when I turned the power down a touch. The weather has stopped me going out today with my garmin speedo attached to get some idea of loss of power on the road. I want to compare my scooter to another bike now as it's been a while since I rode my lambretta, I'm thinking that maybe being on the GTS for work & everything else through the winter has tuned my brain into thinking my Lambretta is under performing & until compare it to another I'll have no idea.

It is frustrating when you buy things to increase performance & over £300 spent for no noticeable improvement.

Are you doing any rejetting with all the exhaust, ignition, air filter swapping going on?
camel
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this filter...is it on a rubber elbow?or a panel filter straight on the carb,because mine will not rev out with a filter that close to the carb,i run mine open with a std mb shorty,my other motor i can run it on a modified mb shorty manifold and a breathe sweet filter.i have no hole in the panel on sx panels so clearance is minimal.
i think your getting there,i never build a motor and find it dosnt need fine tuning,geaing/jetting changes......and please dont compare your lammy to a gts,your talking two different animals.
the kegra pipe...jl2 is a well known on/off pipe...all revs no torque
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Muttley McLadd
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a.j wrote:It is frustrating when you buy things to increase performance & over £300 spent for no noticeable improvement.
:lol:

Is there anyone here that's never done this??
CakeAndArseParty
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