no compression

[fuelcat]

So I got the bike back together and it wont start. thought it could be the carbs but some one suggested putting some gas in 1 and 2 return the spark plugs and if the bike seems like it is going to start then I know it is the carbs. It did not happen for me. A puff of white smoke came out of the air box. I took another look at the timing and it was way off. I dont know how that happened but I fixed it , put the bike back together and still wont start. I trie to do a compression check and it looks like I am not getting any compression. I had changed the rings and honed the cylinders and changed the valve stem seal and adjusted the valves. I felt like like I was being real careful doing all those tasks but something is obviously wrong. Any suggestions for me now? Should I take the whole thing back apart? Can I reuse my head and base gasket that I just replaced if I do have to take it all back apart? Thank you for your help.

[OLDENUFF]

If you have no compression after a top end rebuild, your cam timing is probably off. You have an open valve during the compression stroke. Pull the valve cover and recheck your cam timing. You should be able to reuse the gaskets.

[duaneage]

I've seen an engine pulling air in the exhaust and pushing out the airbox because the cams were in wrong. You should be able to correct this easy.
Tell us what bike, engine you are working on and we can provide some assistnace.

[chef1366]

Take a picture of all the timing marks (cams and ignition) and post them.

[fuelcat]

I have a gs550l 1981. I just checked the timing again and it is off. I am not sure what mistake I am making. I line the t mark up with the little line that is right after the "T" , I take the tensioner off, I turn the #1 with the arrow on the ex flush with the gasket on the front of the engine, I then count 23 pins from #2 on ex to #3 on intake. I recheck my t mark to make sure it did not move. I put the tensioner back on and turn the engine once and it looks like it is lined up. Now I try to start the bike and it does not start ..no compression. I open it back up again to check the timing, I line up the t and now the #2 arrow is flush with the front instead on # 1. What am I missing? what am I doing wrong? This will be the third time at this. There must be one little thing that I am messing up on that makes the timing not work.

[chef1366]

Are you cocking and releasing the tensioner?
Are you on #1 & #4 TDC? It's easy to put the rotor on the end of the crank off 180 degrees.
After timing it the buckets on 1 and 4 should spin and you can see the cam lobes are not pushing down any valves on those two cylinders. If they are pushing down the buckets try puting the crank trigger on the other direction.
Plus are you sure it's 23 pins? I've never heard of a GS having that number.

[Nessism]

23 pins is wrong, should be 20. That may be your problem.

[fuelcat]

Are you cocking and releasing the tensioner?
Are you on #1 & #4 TDC? It's easy to put the rotor on the end of the crank off 180 degrees.
After timing it the buckets on 1 and 4 should spin and you can see the cam lobes are not pushing down any valves on those two cylinders. If they are pushing down the buckets try puting the crank trigger on the other direction.
Plus are you sure it's 23 pins? I've never heard of a GS having that number.

I am cocking and releasing the tensioner. I got the 23 from clymer and the suzuki repair manual for gs550 on BikeCliffs website. I am not sure about being on #1 and #4 tdc? I was just lining up the t so I will check that. Im sorry but I dont know what you mean by crank trigger? This is my first time at wrenching.

[Nessism]

What year 550? The first generation 550 engine (8 valve) is 20 pins. Not sure about the 16 valve engine.

[chef1366]

I am cocking and releasing the tensioner. I got the 23 from clymer and the suzuki repair manual for gs550 on BikeCliffs website. I am not sure about being on #1 and #4 tdc? I was just lining up the t so I will check that. Im sorry but I dont know what you mean by crank trigger? This is my first time at wrenching.

The crank trigger is on the end of the mechanical advance. T mark should also have 1&4 written on it.

[fuelcat]

23 pins is wrong. That may be your problem.

This diagram is from the 850. Your bike is similar except you need to use 20 pins.

Oh ok I will try that. I was going by the repair manual but it must not the right info.

[Nessism]

Okay, checked the 16 valve 550 manual and it's 23 pins.

Which engine do you have?

[fuelcat]

I have 8 valves

[chef1366]

I have 8 valves

Try twenty pins then.

[fuelcat]

Try twenty pins then.

OMG thank you soo much!! I will get back to it tomorrow