still trying to get 450l to start.

[willis1345]

I was on here few months ago seeking some help with my 1983 450L, it won't start and most everybody said it was cause I put pods on and had straight pipes. Well I put some restrictive mufflers on and taped up pods (have no airbox) and all I get is backfiring after cranking on it for while, I have spark at plugs. I am new to this kind of bike but I have good knowledge of bikes in general. I do have a old clymers service manual and have tried test's on igniter and signal generator. Nothing definite there. Is it possible for it to jump time in cam chain area? Im trying to keep this low budget for now until I see if I can get this thing to start. Because I do have spark at plugs, but don't know if firing at right time. Just looking for other things to check before I try getting different parts (igniter/signal gen.)to try and get this thing started. Any help is appreciated.

 

[koolaid_kid]

Pods and a pipe have absolutely nothing to do with starting. They only come into effect when you come off the idle circuit into the needle and the main jet. You need to look elsewhere.
If it is backfiring, you need to remove your valve cover and check the timing of the cams.

 

[willis1345]

Thanks koolaide kid, I will give it a look insde. I'm going to assume there is is some timing marks. Im not familiar with cam chains and such, with my old harley I had it had gear to gear with marks to align. Is there much to these to get them in time? I don't have bunch Of faith in this service manual I have, but it's all I got.

 

[tom203]

Lots of posts on cam to crank timing- don't be intimidated. Bike should start if you have compression, fuel and spark at about the right time- fine tuning comes later.

remove valve cover and signal generator cover- best to remove spark plugs as it will be easier to turn crankshaft to line up marks.

 

[Nessism]

Did you pull off the carbs and clean them? Did you replace the 30+ year old O-rings with fresh? Did you replace the intake boot O-rings? How many turns open are the pilot screws?

Regarding the jetting, at minimum you should move the main jets up three sizes and shim the needles. This is just a starting point for rejetting.

 

[willis1345]

I did go thru carbs and bought some new brass main jets cause old ones were like nylon and were wasted. I know I went up in size but now I can't remember what size old ones were.

 

[willis1345]

tom203 mentioned posts for cam - crank timing. kinda new to forums, what's best way to search for them ? Didn't see anything for searches.

 

[koolaid_kid]

Willis, your Suzuki Service Manual is all you need. It shows how to align the mark on the crankshaft (under the signal generator cover on the right side of the engine) with the marks on each of the camshafts. It is very simple to check and critical to set correctly.

 

[willis1345]

Here's a dumb question, when the "R T" mark is at the mark on the case isn't the right cyl. piston suppose to be a the top of it's travel? I know there is two times the right side piston is up to the top of its travel, but when I bring No.2 up the mark is behind getting to where it's supposed to be. The exhaust and intake cams are correct as far as 18 pins between 2 arrow and 3 arrow. I'm just trying to eliminate timing as one of reasons I can't get this thing to start.

 

[koolaid_kid]

This is what you need to check:
Rotate crank clockwise until the "T" is aligned with the fixed pointer.
On the exhaust cam, the "1" should be pointing forward, parallel to the gasket face
The "2" should be pointing directly upward
On the exhaust cam, the "3" should be pointed at the 18th pin from the "2", and slightly forward.
If all this is correct, your cams are O.K.

 

[willis1345]

Thanks, I'm going back out to garage to check it.

 

[willis1345]

Hey koolaide kid I just checked cams and when they are both positioned like you said the rotor with timing marks on it is coming around behind where it should be. There is the right amount of pins between 2 and 3 and 1 is pointing forward level with case. What it appears to me is for some reason the rotor is out of time. Is it possible for me to loosen the bolt in middle and rotate rotor to correct mark on case? It seems like signal generator would be sparking at wrong time. I might be way off on my way of thinking.

 

[tom203]

Get the "T" mark on crankshaft lined up with pointer, THEN look at camshaft mark #1- if it ain't facing forward and parallel with gasket face, your camshafts are off. Take a pic and post to avoid confusion.

 

[koolaid_kid]

Your camshafts are out of time. Do as Tom directed and you will know how much they are out of time. I suspect just one tooth or you would have put some valves on the pistons, which would not allow it to turn over at all.

 

[willis1345]

Thanks to both of you for advice. I bought this bike at a yardsale for a project, so I have no idea how long it's been since running. From what I can see chain and sprokets look fine, what could cause them to get out of time? Am I able to loosen chain and rotate cams where they need to be? I'll go try and take some photos, is it a big deal to post them? Sorry about all the questions.

 

[koolaid_kid]

No. You will have to pull the cam chain tensioner to give you enough slack, then unbolt the cams, etc. You'll see when you get to that point. First you will need to find out how much to rotate them. Be sure and tighten the cam cap bolts in the correct order; your manual will tell you what order to tighten them.
At least you have lots of experience counting the number of pins, that part is crucial.

 

[Steve]

Thanks to both of you for advice. I bought this bike at a yardsale for a project, so I have no idea how long it's been since running. From what I can see chain and sprokets look fine, what could cause them to get out of time? Am I able to loosen chain and rotate cams where they need to be? I'll go try and take some photos, is it a big deal to post them? Sorry about all the questions.

If you get really stuck, just holler. I am just up the road from you and have been known to visit others to help them. :-\\\

.

 

[koolaid_kid]

Good idea, Steve. Willis, do not hesitate to ask Steve for assistance. He knows a thing or two about GS motorcycles. Or so I hear.

 

[Guest]

It's also possible your ignition rotor is on 180 degrees out of whack.

I know how to set that right on the 80 - 82 450's with mechanical advance, but I'm not sure on how to get that right on yours as it has electronic advance.

However, *after* sorting out your cam timing, if it's still a no go you can try flipping it 180 degrees.

 

[willis1345]

I was kind of wondering if rotor was out. The one thing that I can't get out of my head is the fact that when I have the "R" timing mark lined up the "R" piston is not at the top of it's stroke, I thought that was what TDC meant. I loosened bolt that holds rotor to see if I could turn it and it appears there is only one place it will go. Pete what did you mean by flipping it? Im not able to go out and work on it every night cause I work rotating 12 hr. shifts, so if I don't respond right away it's because I haven't had a chance to try what you all have suggested, which I appreciate all the help. This really is my first time using a forum and definitely not the last. Thanks you all!