I am the owner of a 2008 Suzuki S40 that I have owned since 2009. I bought it with 700 miles and now have 13,000. As much I have the itch for something newer (Yamaha FZ-07) I still do love this bike and want to keep it for years to come.  Sorry in advance if these questions have been answered before. I did multiple searches but wanted a place where all the info could be answered at once.

So here are my questions.

1. I switched to to rotella synthetic oil at 10k. How long should I run this oil before changing? 3k miles? I used to do it at 2k or once a year before with the regular oil.


If you see it start using oil at a faster rate, it's getting old. Otherwise, why get in a hurry?

2. I have never done a valve adjustment or even checked them in 13k miles. They don't make a noise as far as I can tell.  Should I keep this mindset of if it ain't broken don't fix it or should I really be checking?

Unless you're familiar with the sound of loose valves, you'd be ahead to at least check them.

3. How long does the spark plug typically last before it needs replacing? I know in some cars they can go 100k. Are their any plugs recommended or just the factory one?

A spark plug should run a looong time. No reason to not have one in the shop.
Clear the dirt from down around the plug before you pull it.
Antisieze is your friend

4. I replaced the front brake pads at around 8k and changed the fluid. Does the rear brake pretty much last the life of the bike? Mine squeals bad...any fixes?

The tire should be getting worn.. When you have the wheel out, clean the dust out, and if you have a grinder you can taper the leading edges and run a couple of grooves across the faces of the shoes at an angle to shove dust to the outside.

5. How long before the forks need any kind of service?

Barring unforeseen events, it'll last as long as the rest of the bike.

6. Does the belt pretty much last the life of the bike? Just need to check tension?

Yep, but gravel roads will flip rocks on it and punch holes in it and Too Tight will bust them.
Adjusting instructions in Tech section.

7. When should I pull off the clutch case off and inspect the cam chain adjuster? I was thinking around 17,500...is that too long?
Distance Per Trip Average oily s Thought to play a role. But, generally, you start getting over 12,000, it's not a bad idea to look at it and probably install the Verslavy.

8. Do the wheels ever need any special attention...truing or bearing?

Truing? Rarely, bearing, also rare.

9. What is a fair price to pay for a valve adjustment and spark plug change from a private non dealer mechanic?

Why change the plug? Missing?

As long as they will let you watch and see how it is done, whatever you think is reasonable for a One Time expenditure...

10. If I take the bike for a cam chain inspection to a mechanic what do they do? I assume they aren't familiar with the Verslagen1 aftermarket adjuster. Do they just automatically replace the cam chain. How much does that run?

How much does that run?
Call and ask, several places.
Ask if they would install your part.
Some won't.
This is not a technically difficult job.
A place to work and tools will save you Money.
You can buy tools and still save money.


That's all I can think of. Just trying to keep the bike in its best possible shape. I have avoided some of the maintanance checks just because I live in a condo and it's not the easiet place to work on.

Justin,

Thanks for taking the time to answer all the questions.

Some things to point out.

1. I don't really notice the bike using any oil and its been 2,500 miles since its last change. What mileage would you recommend I change it at with the rotella synthetic?

I dunno how many miles synthetic runs. The Dino starts to disappear once I have about 2,000 miles on it and I'm running hard.

2. Is it safe to assume that the factory spark plug can last up to 25,000 miles?

I don't see why it wouldn't. It's not fouling out, but it does fire at TDC, every time, so, it's got 50,000 miles worth of sparking at 25,000 miles.
Doesn't cost anything to swap, do what pleases you, just clean down by it first.

3. Do valves typically become tighter or looser with wear? Which one is more dangerous?
The 05 flattened out the tip of the adjuster. Always got loose.
The 02 seemed a bit tight at 5,000 miles.
Tight is dangerous. Burn valves.

4. I changed my tires at around 10k miles, but thanks for the tip on the rear brake squeal.

5. I was asking for the prices of the spark and and valve adjustment just out of curiosity. I'm pretty hands on and do all the maintenance myself...just living in a condo is not ideal for motorcycle work.

It's your living room...

If you only have a ratchet to spin the motor, probably be ahead to pull the plug.
A bleaker bar lets you stop the crankshaft at TDC and hold it while the compression escapes through the ring gaps.
Before you declare success and button it up, look at the timing marks.
Be gentle putting the plug back in.
Antisieze is your friend.