Timing issue

Message

thedeatons · #61 Post by **thedeatons** » Tue Mar 03, 2009 4:20 am

Hmmmm.... weird.... pictures will tell us a LOT!

peterock · #62 Post by **peterock** » Tue Mar 03, 2009 5:48 am

yup, post up a pic of your cam timing with the marks as well.

MX Quad Dad · #63 Post by **MX Quad Dad** » Tue Mar 03, 2009 4:54 pm

I have seen low comppression numbers when cam timming is extremly off. This is a long thread that Ive been reading all along but to tell the truth I can't remember all that was mentioned and if the timming has allready verified as being correct, I'm sorry for a bad post.

quadsourcemark · #64 Post by **quadsourcemark** » Tue Mar 03, 2009 5:59 pm

[quote name='MX Quad Dad' date='Mar 3 2009, 04:54 PM' post='203528']
I have seen low comppression numbers when cam timming is extremly off. This is a long thread that Ive been reading all along but to tell the truth I can't remember all that was mentioned and if the timming has allready verified as being correct, I'm sorry for a bad post.

I'll post some pics tonight.

Thanks,
Mark

quadsourcemark · #65 Post by **quadsourcemark** » Tue Mar 03, 2009 6:00 pm

QUOTE (MX Quad Dad @ Mar 3 2009, 04:54 PM) <{POST_SNAPBACK}>

I have seen low comppression numbers when cam timming is extremly off. This is a long thread that Ive been reading all along but to tell the truth I can't remember all that was mentioned and if the timming has allready verified as being correct, I'm sorry for a bad post.

I'll post some pics tonight.

Thanks,
Mark

kdeal · #66 Post by **kdeal** » Tue Mar 03, 2009 6:29 pm

GOOD ANSWER. He is right it's called overlap of the valves. The timing has to be off if the rings are good.

peterock · #67 Post by **peterock** » Tue Mar 03, 2009 6:35 pm

When you post the pics, post them with your timing lined up.

2mike18 · #68 Post by **2mike18** » Tue Mar 03, 2009 11:43 pm

QUOTE (kdeal @ Mar 3 2009, 12:29 PM) <{POST_SNAPBACK}>

GOOD ANSWER. He is right it's called overlap of the valves. The timing has to be off if the rings are good.

If the overlap was that bad would he still get the 190psi with out the decomp like he says he can reach before the engine cranks too hard to continue? and at the 190psi it sounds like he is saying it wants to build more compression but he doesnt want to stress the starter? and if I read this right when he connects the decomp back up it only peaks at 30psi way too low to start as we all know. So finally to my question if all that is the case wouldn't the problem be related to the decomp over compensating and dropping the compression too low to start??

I just want to make sure I understand this and that I have been reading this post correctly. I get confused easily too many crashes and hits to the head I guess.

lol

when I built my motor I lucked out and wistech did most the work cause I still had a cast on but this could easily be me on my next motor so Im throwing possibilities out there.

cannondale27 · #69 Post by **cannondale27** » Wed Mar 04, 2009 1:36 am

I agree.So now why.Do you have a cam that is modified?Have you set valve clearance?See the timing of the Decomp affects pressure much less than how much it actually opens the valve.Basicly even if decomp stuck in activated position you should still see about 80psi.

quadsourcemark · #70 Post by **quadsourcemark** » Wed Mar 04, 2009 2:26 am

QUOTE (cannondale27 @ Mar 4 2009, 01:36 AM) <{POST_SNAPBACK}>

I agree.So now why.Do you have a cam that is modified?Have you set valve clearance?See the timing of the Decomp affects pressure much less than how much it actually opens the valve.Basicly even if decomp stuck in activated position you should still see about 80psi.

Well when I lock the decomp open I get over 180 psi. But its hard on the starter so I stop at 180. One of my kids jacked my camera so no pics tonight. I'm sure the timming is fine. It has to be the decomp spring. When its connected 30psi comp. When I unhook it 90psi comp. I lock the decomp lever open 180 psi plus. Maybe its on wrong. It seems to go on one way.

Mark