gs450 start up issues

[jfsebastian]

Will try that and revert to you asap.
Cross your fingers.

JF

[jfsebastian]

Well, tried it only once before the neighbor started complaining, and it sort of huffed and puffed.
I´ll try again tomorrow morning.
Will report back and hopefully it will huff in a more serious way then.
I´d love for it just to run so I can fine tune instead of looking for serious faults.

Did however paint the tank and I think it looks great.
Will do some wet sanding now and put some pics at my blog later.
Have a great weekend and happy wrenching

JF

[Suzuki_Don]

Also have a look at your valve clearances. If they are too tight that will cause hard starting issues.

[RogueZuki]

Not to be an ass or anything like that but does the tank have fuel in it and is the fuel selector turn to the appropriate position? I only ask as you have not mentioned gas at all and the person I bought my bike from tried starting the bike on an empty tank with empty carbs.

I know that when I get frustrated, I tend to focus on only one thing, forgetting the bigger picture.

[jfsebastian]

I had the tank mounted, poured some gas in, put in in RES and tried.
Not sure if the vacuum worked, have not disassembled the carbs after this.

Put a cap of gas directly in the cylinders and Nada.

Removed the tank and painted it today. There should still be some gas in the carbs though.

Don, no, I didn´t check valve clearance. The 450 is a pain to adjust, and I figured that the valves might be OK since the bike has less than 30000 km to it. Was i wrong in assuming this?

The paint job looks great. Check my blog.
Still needs wet sanding and clear coat.

JF

[jfsebastian]

Nope, no ignition yet.
Tried again today with some gas in the cylinders and then tried to fire it up, but in vein.
Any ideas what to check first?
Already checked ignition and it´s OK. New battery fully charged.
Switch on RUN, clutch in and starter runs fine.
What what what???

My tank is finished minus the waxing.
Swing is painted with POR15 and will be on tomorrow.
Bike is ready to roll, if it starts that is.....

JF

[jfsebastian]

Guys
New spark plugs, freshly loaded battery, spark fine - No start.
Poured gas in the cylinders, just half a cap barely and almost nada.
Just a short puff and then the starter just goes on and on.

Can the fact that I have disconnected the brake lights, rear lights and indicators have anything to do with it?

I have checked all but valve clearance but if that was totally off, at least I hope I would get some crappy running but at least a short run.

Any ideas would be really really helpful right now.

The bike has 28 000 km on it (18 000 miles).

If anyone in Stockholm could help me out in person, a bottle of Single Malt(or boose of your choice) is yours when the bike runs.

JF

[Suzuki_Don]

Check your compression Sebastian.

[jfsebastian]

I will have to buy that tool, will do when my daughter is free of the chicken pocks.
Sounds like a lack of compression if all electrical is OK.
What else can it me?

[Suzuki_Don]

I will have to buy that tool, will do when my daughter is free of the chicken pocks.
Sounds like a lack of compression if all electrical is OK.
What else can it me?

Seb has this bike ever run before. If not, then you need to check everything. You don't know what the previous owner may have done or not done.

Check your cam timing.

1. Do Compression test.
2. Remove cam cover and check cam timing. make sure it is timed correctly.
3. Then check the valve clearances and correct if necessary.

The motor needs three things to run. 1. Spark at correct time. 2. Fuel to cylinders in correct amount. 3. And mechanical correctness, i.e. good compression, valves opening and closing at the right time, no air leaks, good exhaust with no leaks, etc.

[jfsebastian]

Don,
I´m off to buy a compression tester right now.
Will check all you mentioned tomorrow.
The bike was incredibly stock. Even the covers on the carbs were there.
Not much done there, I doubt that the Top ever has bene off to check for anything.

Fingers crossed......

Thanks mate

JF

[matt_gs450]

Hi JF.

I hope you get your bike started soon. I'm working on a couple 450s right now as well. One is in the same category as yours: electrical tests out, but no combustion. I pulled the carbs yesterday and see evidence of clogged up passages.

Is there evidence that gas is making its way to the cylinders? Any gasoline smell or gasoline issuing from the exhaust? If not, the carbs could be gunked up and not delivering any fuel. I apologize if this was asked and answered elsewhere in the thread.

Good luck!
Matt

[jfsebastian]

Sad news

I tested the compression today and right cylinder had 9,5bar or 9,5 kg/cm2 or 140 psi.
The left had about 8 bar.
Poured some oil in the cylinder and whoops, 9,5 on that one too.

Seems like I need to get new piston rings.
This is not a valve issue, am I right???

What do I need to buy?
What kind of gaskets, rings, tools etc?
Any advice?

JF- **** that the bike is crappy, slightly glad that I get to tear the engine apart and learn that too

[Suzuki_Don]

Seb,
The optimum compression for the GS450 is 130 to 170 psi and the serviceable limit is 100psi. You appear to have 140 psi on one cylinder and 120 psi on the other. That should be enough compression for the bike to start.
Check the cam timing. You only have to remove the tank, cam cover and the points cover to check it. The manual I gave you tells you how to line it all up. And while the cam cover is off check the valve clearances at the same time. You may have lower compression on one cylinder because there is not enough clearance on the valves and one valve is being held partly open and therefore losing compression.
Have you had the carbs off. If not give them a good clean and replace all "O" rings. Check float level, etc.

[jfsebastian]

Don and bmac

Will do that tomorrow morning.
Thanks for being persistent about the valve clearance.
I promise I will learn how to listen soon.....:-)

Hope the Suzuki dealer have the shims in stock if that is needed.

JF