This is how lean, the stock M50 is

[07M50Limited]

Did my 4000 mile today, and plugs are white, they have leaned these bikes down so much!!!!!
Good news was valves are still good...I did them at 600 miles, will check them again, on next service.
Next, I will install the TFI, and fix this lean running bike.
I have a stock 07, only thing done(so far)...is pipes are drilled out with 6 -3/8 holes in each.
Heres a few pic's...dont worry...it goes back together..lol

[07M50Limited]

This will add the needed fuel

[diamond_jim]

Ha ha.

Yours:



Mine:

[Easy Rider]

Originally Posted by 07M50Limited

Did my 4000 mile today, and plugs are white, they have leaned these bikes down so much!!!!!

And you think the appearance of those plugs is bad.......why?

They are not burnt white, with worn electrodes from running too hot......
They ARE pristine white, just like they came out of the box.

It looks to ME like the mixture is just about perfect.

[07M50Limited]

Originally Posted by Easy Rider

And you think the appearance of those plugs is bad.......why?

They are not burnt white, with worn electrodes from running too hot......
They ARE pristine white, just like they came out of the box.

It looks to ME like the mixture is just about perfect.

It hard to tell in the pic they have a crusty white, and I have always, tuned bikes and cars, for light tan. will have to see how they look at next service, Im putting new ones in, and the gaps are burnt

[07M50Limited]

I didnt need it but, found another handy item that fits lifter stud...a sloted, phillips head bolt with a couple nuts on it....dig thur your nuts and bolts, and you have a tool.
Suzuki knows how lean they run and even warn you to switch to a colder plug. in the manual

[Ray Nielsen]

Your plug insulators look good to me. One way to check mixture is to examine the interface between the ceramic and the plug body way down inside where they meet. You'll need a light and a magnifying glass to do so easily. You're looking for a "soot ring" which forms as the burning mixture expands into the plug body. It should be visible as a black sooty ring. If it's solid black it's rich, very wispy looking or missing it's lean.

This technique was espoused by Gordon Jennings a writer and knowledgeable engineer quite a while back in Cycle magazine. It will require a new set of plugs, running at highway speeds for a few minutes and then a stop to examine the plugs.

The modern, fuel injected Japanese bikes usually show clean, white insulators as yours does. With NO lead in the gas the coloration is missing as in older times.

Another examination that may give some imformation is to look at the edge of the center electrode where it's square. There should be an area where deposits are burned off, about a half millimeter down the electrode. Much more or less indicates too much or too little ignition advance respectively. On the M50 timing is not adjustable, rather being controlled by the ignition module under the seat. Still it's worth examining.

Ray Nielsen, in Minneapolis.

[07M50Limited]

Originally Posted by Ray Nielsen

Your plug insulators look good to me. One way to check mixture is to examine the interface between the ceramic and the plug body way down inside where they meet. You'll need a light and a magnifying glass to do so easily. You're looking for a "soot ring" which forms as the burning mixture expands into the plug body. It should be visible as a black sooty ring. If it's solid black it's rich, very wispy looking or missing it's lean.

This technique was espoused by Gordon Jennings a writer and knowledgeable engineer quite a while back in Cycle magazine. It will require a new set of plugs, running at highway speeds for a few minutes and then a stop to examine the plugs.

The modern, fuel injected Japanese bikes usually show clean, white insulators as yours does. With NO lead in the gas the coloration is missing as in older times.

Another examination that may give some imformation is to look at the edge of the center electrode where it's square. There should be an area where deposits are burned off, about a half millimeter down the electrode. Much more or less indicates too much or too little ignition advance respectively. On the M50 timing is not adjustable, rather being controlled by the ignition module under the seat. Still it's worth examining.

Ray Nielsen, in Minneapolis.

Thank Ray, I took a look they were white all the way to the body, I replaced the plugs and added the TFI, I will ride a 100 miles and re-check them.I know its getting more fuel now.