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timing question.
Anthiron - October 22nd, 2004 at 01:08 PM

ive got a 1600 single port with a 30 pict 2 carb and 009 dissy.

im running premium unleaded with additive and was wondering what people would suggest for timing.

at the moment no.1 cylinder fires at the 2nd notch after TDC on the crank pulley. which is 10 degrees ATDC i think. however if i rev it up and let the revs fall quickly i can smell unburnt fuel. however if i retard the timing a little it wont run as well. should i advance it further?

im a complete noob to timing so bear with me please.

Nick

Craig Torrens - October 22nd, 2004 at 02:17 PM

7 1/2 deg BTDC static.

Anthiron - October 22nd, 2004 at 08:18 PM

ok thanks craig

11CAB - October 22nd, 2004 at 08:26 PM

If you mean the notch on the R/H side of the TDC it is before top dead centre. As the crank turns, that notch goes past the split in the case first.....so it is before TDC.
7.5 BTDC is the factory spec, but you can get away with 10BTDC, but you should check the full advance which shouldnt be more than 32 BTDC

Eirinn - October 25th, 2004 at 01:26 PM

yeah i meant before TDC my error. it actually wont run as well at 7.5 ive got a flat spot down low which gets better at around 10-11 BTDC and at about 12 BTDC it advances great but ive lost some top end power so i have it at about 10BTDC.

by the way this is nick on eirinns account.

Nick

Anthiron - October 26th, 2004 at 10:40 AM

ok now ive not changed the timing and the car ran fine all weekend and then this morning i just drove to the shop to get some bread and theres a flat spot down low again :cussing the dissy was tight so i dont think its slipped though i will go check. this is pissing me off.

BiX - October 26th, 2004 at 11:20 AM

What about points, are they new or have they slipped?

Anthiron - October 26th, 2004 at 11:25 AM

the points are like new and i have them set at .016 perfect.

BiX - October 26th, 2004 at 11:36 AM

just a thought i had the problem of the points moving and therefore effecting everything. You just need a big set of carbs so you get rid of the flat spots!!!!

Anthiron - October 26th, 2004 at 11:54 AM

yeah i have a feeling the 30 pict 2 is a bit small. hopefully when i get the type 4 2 litre in it will fix my engine woes but i doubt it. and thats not going to be for a while.

Craig Torrens - October 26th, 2004 at 12:38 PM

Quote:
Originally posted by Eirinn
yeah i meant before TDC my error. it actually wont run as well at 7.5 ive got a flat spot down low which gets better at around 10-11 BTDC and at about 12 BTDC it advances great but ive lost some top end power so i have it at about 10BTDC.

by the way this is nick on eirinns account.

Nick

if your carbie as been tuned/adjusted to the incorrect timing............then it will not run as well if you then change the timing !!
Set the timing and then adjust your mixture/idle screws.;)

Anthiron - October 26th, 2004 at 01:53 PM

i didnt think that mixture would change much cause i was only changing the timing by a few degrees but i was wrong jesus it was way out adjusted the mixture and its a rocket again. thanks craig. one thing i have noticed lately though it that when i shut off my engine it makes a "pssss" noise for a second as though pressureised gas is escaping from somewhere. can anyone explain this?

Craig Torrens - October 26th, 2004 at 02:22 PM

no worries;)

koolkarmakombi - October 26th, 2004 at 02:47 PM

Quote:
Originally posted by Anthiron
one thing i have noticed lately though it that when i shut off my engine it makes a "pssss" noise for a second as though pressureised gas is escaping from somewhere. can anyone explain this?



one piston will be on a compression stroke, that will leakdown and you will hear it from the case breather.

:beer
kkk

Anthiron - October 26th, 2004 at 02:54 PM

ok cool. thanks