my malossi cylinder zip sp what wrong it is

[WDJ]

hello,everyone,my scooter has a fault now.what it is?
high temperature for the combustion chamber?
bad oil? (i use motul 710)
the timing is wrong?

 

[jog rr lc]

By the looks of things their is no lubercation in the cylinder.
do you still use separate oil tank or do premix ur oil an fuel?
'srry for bad spelling'

 

[WDJ]

By the looks of things their is no lubercation in the cylinder.
do you still use separate oil tank or do premix ur oil an fuel?
'srry for bad spelling'

i use the mixed fuel,the 33ML oil for the 1L gas.

 

[RobinL]

That is a good mixture (maybe a little too much oil, but that's better than not enough).

What colour is your spark plug? Looks like you have been driving with a poor mixture (air/fuel).

 

[WDJ]

That is a good mixture (maybe a little too much oil, but that's better than not enough).

What colour is your spark plug? Looks like you have been driving with a poor mixture (air/fuel).

spark plug is bad because the piston is melt with high temperature, so can'nt look the colour.
i use a dellorto phbl 25 carb,main jet 130#,the spark pulg colour is brown in the running,it's a good colour i think.
but in the racing i just drive about 2 minutes,the cylinder on the bad:?

 

[47lamy]

Thats Detonation, The jet should be ok on the carb so it could be an air leak or fuel starvation, or ignition could be far out? Whats your ignition timing?

 

[WDJ]

Thats Detonation, The jet should be ok on the carb so it could be an air leak or fuel starvation, or ignition could be far out? Whats your ignition timing?

malossi assembly instructions writer the timing is 16°
i don't know what i do right
the picture is my scooter,when the Pistons in the TDC this angle is 16°, is it right?

http://img528.imageshack.us/img528/1441/80091849.jpg

 

[tiba_karotsu]

pre-ignition leading to detonation, your cooling system is not sufficient enough to remove the heat from the cylinder, you must add another radiator to compensate for the extra power.

also you may be jetted too lean which would also do that.

 

[apriliafan]

Jetting I d say.

What spark plug u ve used?
Br 8....?^^

 

[WDJ]

pre-ignition leading to detonation, your cooling system is not sufficient enough to remove the heat from the cylinder, you must add another radiator to compensate for the extra power.

also you may be jetted too lean which would also do that.

i used a hexagon 125 radiator and dellorto phbl 25 carb 130 main jet.
i think the main reason is pre-ignition leading to detonation.

 

[WDJ]

Jetting I d say.

What spark plug u ve used?
Br 8....?^^

ngk 9eix

 

[tiba_karotsu]

i used a hexagon 125 radiator and dellorto phbl 25 carb 130 main jet.
i think the main reason is pre-ignition leading to detonation.

with the power you're making even the hexagon 125 radiator is not sufficient to cool your cylinder, you must add another radiator to keep your temps down to acceptable levels or just keep replacing pistons after a few kms.

 

[WDJ]

with the power you're making even the hexagon 125 radiator is not sufficient to cool your cylinder, you must add another radiator to keep your temps down to acceptable levels or just keep replacing pistons after a few kms.

i add a another radiator now,is it OK?
are there any other good suggestions?

 

[tiba_karotsu]

good but make sure you bleed out all the air inside the cooling system. by the looks of it you have just increased your cooling capacity by 50%, i think that should be enough.

good luck with tuning & use a colder plug like a 10 or 11.

 

[WDJ]

i see the sip-scootershop, why the malossi mhr team piston has 4 choice(A\B\C\D)? what are those distinction?
i want buy one and which one should I choose?

http://www.sip-scootershop.com/Products/M348654/Kolben+MALOSSI+MHR+Team+68ccm.aspx

 

[tiba_karotsu]

A is the standard size, B C D are slightly bigger to account for bore wear.

it's like this;

A = standard size
B = +0,01mm over standard
C = +0,02mm
D = +0,03mm

 

[WDJ]

i see and the 0.01\0.02\0.03 is the actual size? is not assumption of you?

 

[tiba_karotsu]

i see and the 0.01\0.02\0.03 is the actual size? is not assumption of you?

not like that, it's like this.

47,54mm = A (standard)
47,55mm = B (+0,01mm)
47,56mm = C (+0,02mm)
47,57mm = D (+0,03mm)

 

[WDJ]

i see, thank you very much!!