240 Mugello Runing hot and being stubbon to jet.

[Frautzi]

Hi all, struggeling to set up my 240 its proving difficult to jet between needle and atomiser (just over 1/4 to 3/4 throttle) and the plug showing its lean and running hot. If i go any higher on the jetting with needle or atomiser the scoot just bogs and sounds like it's breaking down and wont pull clean unless i drop a gear and feather it through to full throttle. once it clears to full throttle the thing is flying but its only got 35 mile on since rebuild and i need to get it something like so i can run it in properly.

Its running very hot and i've got combinations of x7/x13/x2 needles and av264/266/268 atomisers.

As far as i can tell theres no air leaks.

The only differnce with this set up and its original set up is the skirt length is longer by 2mm and it was originaly running a 42mm ancillotti.

Help any one??

Cheers Jay


Set up:
30mm Delly filtered
60pilot
Av264
x13 needle second clip
130main
350 fuel valve
camlam fast flow
Mugello 225 Touring tune by chisel speed
70mm Ron Moss Avanti Piston (cut skirt by 2mm)
62mm full circle crank
107rod
Head reprofiled by Harry Barlow Proporting 1.3mm squish
BGM 80w stator
Af Light Fly wheel
Blue CDi
Ngk N9 Plug
50mm Gori Exhaust.
19/46 on a GP200 box
I have had the timing at 18 / 17 and 16 deg BTdC

[coaster]

Are you running it through a filter on an elbow? just wondering if it's blow back at a certain point in the revs. Try it open mouthed and see if it improves. If you are already running open mouthed then check how close the carb is to the panel. Just some thoughts

[Frautzi]

Are you running it through a filter on an elbow? just wondering if it's blow back at a certain point in the revs. Try it open mouthed and see if it improves. If you are already running open mouthed then check how close the carb is to the panel. Just some thoughts

Hi mate yep its on an elbow and there is some blow back when it reves. if i take the elbow of it reves clean on the ramp, i will give it ago whithout the filter, but i realy want it filtered.

Cheers

Jay

[byron]

I generally use an 8 plug on chop rides
it responds more, and sooner, than a 9...

you set the timing with a strobe ?

[Frautzi]

I generally use an 8 plug on chop rides
it responds more, and sooner, than a 9...

you set the timing with a strobe ?

ok i have an 8 i will give it ago. yes should of mentioned the strobe

Cheers byron

jay

[michele]

i think is really to line with a 130 main

[chisel]

you should try a smaller pilot ,around 48 to 50 and the av268 atomiser,it'll be running hot because its too lean on the atomiser,but you are making it act rich with too big a pilot,once you have the midrange something like you may well need to go down on the main jet,but you'll have to chop it to see.the other thing you don't list is what slide cutaway you're running,this also has a big influence,i would think a 45 will do the trick with a right-angle filter setup

[Frautzi]

you should try a smaller pilot ,around 48 to 50 and the av268 atomiser,it'll be running hot because its too lean on the atomiser,but you are making it act rich with too big a pilot,once you have the midrange something like you may well need to go down on the main jet,but you'll have to chop it to see.the other thing you don't list is what slide cutaway you're running,this also has a big influence,i would think a 45 will do the trick with a right-angle filter setup

Hi thanks for the reply, its running a 40slide as originaly set up by Chiselspeed

60pilot
AV266
X7 second clip
130main

I have taken the filter off tonight and it flys but its still flat around 1/2 to 3/4 and you have to feather it through. I really want to run it with the filter as its quite heavy on spit back.

I will try and get the mid sorted as you suggest. Just a question how long should it take to colour a plug?? instant or a few miles at a held throttle position?

Many thanks and much appreciated
Jay

[chisel]

one thing you don't say is if the engine originally had a 62mm stroke or was it 58mm?because if the barrel was done for 58mm stroke then you would have much greater inlet timing now due to the increase in stroke added to by the 2mm off the skirt so no wonder a lot of spit back if thats the case.
as for how long to get a colour you should get a meaningful one with about 5 or 6 miles running,but getting a colour to tell you midrange is not very easy ,unlike a full throttle chop for the main jet.

[Frautzi]

one thing you don't say is if the engine originally had a 62mm stroke or was it 58mm?.

The engine was originally done for the 62 crank,and a barrel base packer the asso piston that was with it had 4mm off the inlet which gave it quite a large inlet duration, i have put a replacement Avanti 70mm due to the fact the asso had been damaged by the crank weight coming loose and being distributed up the transfers.

see here:

http://scooterotica.org/forum/viewtopic.php?f=7&t=16211

Original Spec
Mugello 225 Cylinder (Touring Tune) 238.63cc
Asso 70mm Piston
Chiselspeed Modified Head
Casings/Manifolds matched to cylinder
62mm Full Circle Crank - 107mm Rod
GP200 Gear Box
19x46 Sprockets
12v Electronic Ignition
BGM 80 Watt Stator
Italian Regulator
Ducati CDI Unit
Ancillotti Exhaust
6 Plate Clutch
Dellorto PHBH 30mm Carb
Ram Air Filter

Thanks for the reply
Jay