why no compression

no matter how hard I try, I cannot get this thing timed right... I have a compression tester but no matter how I adjust the chain I can't get compression...maybe I should just try to start it but I can't see why I wouldn't have compression. 81 650 CSR. Can someone explain the T|F|1-4 marks to me or give me some Idea what I'm doing wrong? how do you know which revolution to time the crank on? I'm uber frustrated...

you will want it on the T mark thats the top dead center for cyclinders 1&4 which is what you use to set the crank in time with the cams. Use a service manual it explains how to do it. and DONT START IT!!!!!!!!!!! if you do you will blow it up, if the timing is out. If your timing is right via the manual. then you might not have commpression for other reasons.

I have a manual. It's not super descriptive on where in the 720 degrees that the crank seems to have as part of rotation. apparently there are 2 rotations of the crank that you can land on. I seem to have tried both but still don't have any considerable compression. Anyone know how to basically explain "timing a csr 650 for dummies?" I need a new perspective. no offense but please don't tell me to read the manual...I did. either something is Fubar or I need to look at it from a new angle. Any and all help is greatly appreciated.

I may be wrong, but I don’t believe the 720* matters. When the crank rotates into a position where the #1 and #4 pistons are up (for simplicity lets’ call this 0*) both #1 & #4 spark plugs fire; this happens every 360* of crank rotation. So it doesn’t really shouldn’t matter whether # 1 cylinder is on its compression stroke or #4 is on its compression stroke stoke; whichever one is will fire because that will be the one containing the compressed air/fuel mixture. In other words, even though there is 720* of crank rotation between each compression stroke (and subsequent power stroke) for a given cylinder, the spark plugs fire every 360*. As a result, as long as the cams are properly timed with the “T” mark on the timing advancer you should be ok. Sorry I don’t know how to explain this clearly; hopefully someone else with better writing skills can. Ed

Ya i think i would go from T on 1&4. and if you still dont have compression and no interfernce with valves hitting or hitting pistions while cranking by hand. there is probably something else wrong. Have you had the bike running before? if not theres a few things it could be besides timing. like bad rings or the valves not shutting all the way.

.

Just looked it up go to T on 1&4 make sure it lines up with your mark,make sure the arrow on the exhaust cam sprocket lines up with the front of the head and it is parralel with the top the head. then make sure the intake cam sprocket arrow faces the rear parralel with top head the same as the front just facing the rear instead foward.then look at the exhaust cam and see the pin on the cam chain that is excatly even. that is 0 start with the next pin up as 1 then count 36 pins and it should line out with the arrow on the intake cam

Powerstroke_fan wrote: Just looked it up go to T on 1&4 make sure it lines up with your mark,make sure the arrow on the exhaust cam sprocket lines up with the front of the head and it is parralel with the top the head. then make sure the intake cam sprocket arrow faces the rear parralel with top head the same as the front just facing the rear instead foward.then look at the exhaust cam and see the pin on the cam chain that is excatly even. that is 0 start with the next pin up as 1 then count 36 pins and it should line out with the arrow on the intake cam

X2

did u check the valve clearance? if u have no clearance u may have no compresion.

TorreyJ wrote: no matter how hard I try, I cannot get this thing timed right... I have a compression tester but no matter how I adjust the chain I can't get compression...maybe I should just try to start it but I can't see why I wouldn't have compression. 81 650 CSR. Can someone explain the T|F|1-4 marks to me or give me some Idea what I'm doing wrong? how do you know which revolution to time the crank on? I'm uber frustrated...

I don't think it matters as long as you are at TDC. At least it doesn't on mine.

Torrey, not being a jerk here do you have a shop manual? It would save you a ton of frustration I can send you some info out of mine but I have a 77 kz1000 not sure how close they are. Wont be home for another 3 hours.

Totally get a manual. you see, i rebuilt a suzuki 8 valve engine DOHC and i didnt take the rotation of the crank itself into consideration. I just lined up the cams and counted the chain pegs over to the other cam. Trust me, got a nice clunk when i turned the motor over (luckily didnt bend the valves). Have you had this happen to you? Not trying to instill fear but if you rotated the motor after attempting to time it and it stopped and made a "clunk" noise.. you could have bent the valves if you were cranking on it hard. best bet is to get a book on the bike and figure it out for sure. I couldnt time my suzuki for the life of me till i got the manual you can probably get a clymer or somthing like that for free on the internet if you computer can read PDF files. Good luck man.

oops sorry i didnt read before i posted that. I had trouble even AFTER i had the manual. Took me about 4 tries. I would pull the head off and make sure the valves are seating like they should. I hope you get your sickly beast feeling well again