no fuel into cylinders?

[Jerkeife]

Hello everyone,

Last fall i bought my motorcycle very cheap from a guy who couldnt get it running right. I took it home and noticed that he had the 3 and 4 spark plug wires switched and the number 2 spark plug was barely turned in. Fixed those small issues and the bike ran great.

Since riding season in Wisconsin was over and since the po mentioned that he had the carbs off and apart i decided that i should prolly start tearing it all apart because he couldnt figure out ho to put a spark plug in. anyways i have put the bike back together and cannot get it to start. It will crank and crank and crank and just not start. So far this is what ive checked...

1) the carbs are getting fuel. I know this because i can open the float bowl drain screws after i prime it and fuel pours out.

2) there is spark (and good spark) i pulled each spark plug out and held it against the valve cover and there is spark

one thing i noticed with the plugs was that they was virtually no fuel on them. so i partially filled the bowls with fuel and then inplugged the fuel lines from the petcock and attempted to start the bike. after 45 seconds of cranking the engine i stopped and opened the drain screws again. there was quite a bit of fuel in every bowl.

this leads me to believe that there is a timing issue. the exhaust pops when i attempt to start the bike but i do not believe that there is any a/f getting into the cylinders. i have not attempted to change the timing or anything as of yet but any help would be greatly appreciated.

thanx everyone!

[The CyberPoet]

Is the fuel fresh? If it's left over from last fall, that could be your culprit right there...

The other question is whether it's generating enough vacuum to pull the fuel up through the carbs....

Cheers
=-= The CyberPoet

[Jerkeife]

fuel is three days old so i hope so. as for the vacuum i just gave it a quick test. i plugged the vacuum hose from the carb into the petcock and cranked the engine with the petcock in the run position and no fuel came out. loss of vaccum could b the culprit. any ideas for a vacuum loss? i only have the headers on for the exhaust but that should have nuttin to do with vacuum. thanks cp

[squiggy]

Will it start or attempt to start with starting fluid? You mentioned about a pop in the exhaust so if it wants to start with starting fluid then it's fuel delivery related.

Timing is essentially mechanical related, so if was working before, like you stated, then there is/was nothing that altered the timing on the engine now.

[Jerkeife]

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Timing is essentially mechanical related, so if was working before, like you stated, then there is/was nothing that altered the timing on the engine now.

i had the intake camshaft off and marked the chain and shaft with paint marker but maybe sumhow i screwed that up...

[The CyberPoet]

i plugged the vacuum hose from the carb into the petcock and cranked the engine with the petcock in the run position and no fuel came out.

Well, that's what supposed to happen -- no vacuum to the petcock, no fuel. But did you feel any vacuum at the hose, and/or if you put your hand in front of the airbox, can you feel it sucking steadily during cranking?

ALSO: if you left old fuel in the carbs over the winter without running the bike, although the fuel that's in there now is fresh, the old fuel may have still left behind fuel residues (sticky gum) that clogged up the pilot jets -- resulting in not running (insufficient fuel getting into air as it goes through the carbs). Ditto if there's any tank rust (rust debris clogging the jets). That would leave you with health spark, healthy vacuum, healthy fuel going to the carbs, but still give you these symptoms.

Cheers
=-= The CyberPoet

[Jerkeife]

i completely took the carbs apart and cleaned them so no old fuel or gum in the carbs. went to check the vacuum at the filter and there is some pull there. idk what it feels like at normal so i cant judge but when i cranked it sparks flew out of the exhaust.

[kevin2502000]

i had the intake camshaft off and marked the chain and shaft with paint marker but maybe sumhow i screwed that up...

That is not the way to time it. I will almost guarantee it is off a few teeth. I tried to do that in my younger days before I found out about the slack in the cam chain and the tensioner. Get the manual or download the procedure from here. If the intake cam is off a few teeth then the exhaust is of twice that much. At least you didnt bend valves...........

[squiggy]

i had the intake camshaft off and marked the chain and shaft with paint marker but maybe sumhow i screwed that up...

It's possible. There are timing marks on the chain, intake cam and the exhaust cam. They could be off. Like Kevin stated, obtain the manual and it will show you the proper settings for the timing. Or at least you'll doublecheck your marks are correct and eliminate the potential timing issue.

[Jerkeife]

i have the manual on here and a paper manual (cylmer i think) so i will check the timing this weekend and let everyone know how that goes...at least i dont have to take everything off to get to the camshafts. thanx everyone

[Jerkeife]

hey everyone im sure this will b merged but i fixed the timing and it fires right up now! thanx for the help!

[squiggy]

Cool.