Alright, this is my first post of this forum and I am beyond grateful for what I have learned from the rest of these Suzuki masters on this site already.

I bought an '08 S40 for what I thought was a deal at $500 bucks. It is my first motorcycle and so like most newbs I am not only unfamiliar with terminology but the basic mechanics of a motorcycle as well.

After frequenting this site and as many other videos on the web, I feel at least a little accomplished in not being as shy around the machine as when I had first made the purchase. But, I still have not had any luck in getting the bike to fire up.

I am not sure of all of the work that was done to the bike before it became mine, but for the most part it looks like the previous owner put on a straight pipe and fiddled with the carburetor since the brass plug for adjustments had already been pulled.

Since the wiring harness was seemed shot and honestly pretty bootleg I opted for a second hand wiring harness rather than tackle that mess.

Now after a new (to this bike) wiring harness, starter relay, ignition coil, R/R, battery, spark plug and OEM muffler and a carburetor cleaning..I don't know what else to work on to get it to run.

After turning key in ignition I get lights, after hitting start button the I hear a click and then just a whir whir whir sound of the starter and then like a thump like it missed it's firing cycle.

Fresh gas, nice big blue spark....but still no clue.

I'm thinking it may be a badly adjusted decompression...thing...but im not sure how to go about straightening that out..it gives a little upon cranking the ignition but there is a little slack in the decompression cable.

Any thoughts?    

Thanks for the intro neighbor. I would be interested to have this group in all the same room and see how it goes  

I have gotten the engine to run once, maybe twice, but only momentarily. The bike would die oddly once if I let off the throttle. The next time it died when I gave it throttle.

I double checked all over the wiring harness and believe that all should be well on that end. But I am by no means knowledgeable about amps and volts... Starting fluid won't do the trick.

The chrome covers are off as well so I could see the decomp. lever but it barely twitches. Doesn't act as you explained.

I am not sure about the jet sizings. Maybe the prior owner swapped when they installed the straight pipe. But that is beyond my understanding. I suspected a dirty card so I had taken it off to open it up and clean it (noting how things came off/went back on ) and i've read all manuals to make sure that the hoses are properly placed.

Only thing I may have forgot to mention is that i'm guilty for not knowing about the Raptor petcock and got another manual that fit. But fuel still flows when set to prime and I have the vaccuum plugs capped off.

How can I help avoid cranking with no oil on cylinder walls? Any product recommendations?

And with brand new battery (bought yesterday) I get my multi meter reading at 12.4 with keys in on position. While trying to crank engine over reading falls to under 10 maybe under 9 volts. This eventually depletes the battery.

So back to let's say full battery, I have a plug in the port and another in the boot. Cranking over shows nice blue spark but it's not enough to fire up with what I believe is good fuel flow to the carburetor. Of course choke is out when attempting to start.

I feel like I have the gas, the spark, and I don't have a modified air intake so I don't know what's the issue. Previous post shinned the light in decomp lever not acting correct while engine cranking but I don't know what's causing it not to engage

Shot of ether doesn't seem to do the trick  

But I will try and re-orientate the front wheel to a higher position to spread the oil around.

Definitely going to drain the bowl and check for amount of fluid. I had opened it up to see a drain but didn't confirm amount in float bowl.

Hoping it's not to do with compression...that just sounds like a wicked problem to have

If your voltage is dropping that much when you crank the engine - the ignition system cannot create a spark with that low of voltage.

What do you know about the battery.....how old is it?  Have you tried jumper cables to a car battery (do not run the car when you jump a motorcycle).

I suspected compression a little while back and bought a tester. Dumb me happened to get one that doesn't fit. I haven't gotten back around to picking up the correct part and actually testing.

The old battery would drain in volts when connected to the multi meter with key in both on and off positions. Steadily dropping before trying to start it up and doing more so when I did try to turn it over.

I just just bought this new battery now maybe two days ago. It is a Yuasa electrolyte battery.

I asked the guys behind the counter and they said after filling the empty battery there during the sale that it should be about 85% charge.

After installing the new battery when I got home it read 12.3 volts key in off position.. floating between 12.2 - 12.1 with key in on position.

Multi meter dipped to high 9's low 10's when hitting the starter.

Didn't keep on it to save the battery.

As far as the Petcock, it was labeled a manual petcock on Amazon but when I reviewed it it had the carb line and what I thought was a line for the vacuum. It also has and ON and PRI position.

I connected it like the OEM setup to try that first and no start.

After that I just set the valve to PRI and plugged up the little ports to remove the vacuum aspect. (Covering the extra line on the petcock and the vacuum on the carb)

Sorry for any confusion

filling the empty battery there during the sale that it should be about 85% charge.


That's your clue to charge it.

Charge the battery