What maintenance to do while bike is torn down

[drychain]

OK, so I bought a 2008 ninja 250r w/ 32.000kmfor my first bike back in fall. I bought it not running (properly). The previous owner had overfilled the engine oil so much that it got sucked into the airbox where it leaked out and plugged the filter. The result was a leaky bike that didn't run right so I got it cheap.

I did do a compression test which came to about 125-130psi

Here's a list of things I've done, or am planning to do still.

1. Change engine oil & coolant, spark plugs, air filter

2. Rebuild carbs

3. Rebuild front shocks

4. Replace worn brakes (not sure if discs are shot, will need to measure)

5. replace rear, possibly front tire.

now, is there any way I can tell whether the rear shock is shot without riding the bike (and putting it back together first)? Since oil leaked from the airbox the shock is covered in oil as well.

Also, if not necessary, id rather not do a carb sync and valve lash adjustment as those are both very lengthy procedures.

Is there anything I am missing??? Anything that should be done while I've got the bike torn apart?

Any input is appreciated, thanks!!

[Ceeloo Yello]

I am currently doing swingarm, uni track, servicing as well as wheel bearings.

[drychain]

Thanks, how many km's is your bike at?

[Ceeloo Yello]

Sitting around 7200 miles.

[DannoXYZ]

With 32 000km on clocks, without any records, you should at least measure valve-clearances. Not that difficult at all with feeler-gauges. Only if they are out of spec would you need to remove cams to adjust. These bikes run like crap when valve-clearances are out. You also risk burnt exhaust-valves; very time-consuming and costly to repair.

[drychain]

Thanks, C

[drychain]

Originally Posted by DannoXYZ

With 32 000km on clocks, without any records, you should at least measure valve-clearances. Not that difficult at all with feeler-gauges. Only if they are out of spec would you need to remove cams to adjust. These bikes run like crap when valve-clearances are out. You also risk burnt exhaust-valves; very time-consuming and costly to repair.

Alright, I guess ill have to do that then. I don't like taking off heads as to not contaminate anything but oh well.

Also, since the engine probably burnt some oil from the soaked filter, there's probably a lot of carbon in there. Any suggestions for removing that other than giving it some seafoam when it's running? thanks for the input!

[DannoXYZ]

No need to remove heads to measure valve-clearances. Just take valve-cover off top and you can slide feeler-gauges between cam-lobes and valve-buckets. Procedure's in manual and very simple.

Seafoam is pure snake-oil, stay away! As test, pour some Seafoam on asphalt surface and watch what happens. NOTHING! Pour some Techron concentrate on asphalt and you'll see it start to dissolve! Absolutely ONLY cleaners that actually work is those with high levels of PEA - PolyEtherAmine (+50%). Might be only 5 products on market that has high enough levels of stuff to actually work.

- Red Line SI-1
- Techron Concentrate Plus fuel-system cleaner
- 3M Max Strength Fuel System Cleaner #08814
- Royal Purple Max Atomizer 18000
- Gumout All-in-One (they've reduced PEA concentration in recent years, might be off this list soon)


BTW - Seafoam is proof that marketing works; snake-oil from gypsies, selling ice-cubes to Eskimos! It's similar to the '80s marketing campaign for STP Oil Treatment. Ended up costing Granatelli millions and millions in class-action lawsuits...

[drychain]

Thanks for your reply!!
yes I meant valve cover not heads, got those mixed up. The manual calls them head covers so maybe that’s why...
And I’ll get some techron cleaner. Do they sell that at the chevron gas stations?

[DannoXYZ]

Sure I think they have them at Chevron stations. There’s several varieties. Be sure to get “Concentrate Plus”.

[jkv45]

Originally Posted by DannoXYZ

Sure I think they have them at Chevron stations. There’s several varieties. Be sure to get “Concentrate Plus”.

I use Techron Concentrate at 1oz per gal (now renamed Complete Fuel System Cleaner, I believe) in all my vehicles once per season.

It was suggested to me by a Mechanical Engineer friend that works in the auto emissions testing industry. Not someone that's swayed by hype, or is easy to impress.

In their tests it cleared heavy deposits on valves and in the combustion chamber in one tank.

He was impressed.

[drychain]

Originally Posted by jkv45

In their tests it cleared heavy deposits on valves and in the combustion chamber in one tank.

Perfect, that's what I need. Now, assuming that there's a lot of deposits on the valves, wouldn't that affect my clearance measurements? Like I said there was lots of oil and crap in the airbox so I'm sure some of that made it into the engine??

[drychain]

Originally Posted by DannoXYZ

Sure I think they have them at Chevron stations. There’s several varieties. Be sure to get “Concentrate Plus”.

I will, thanks!

Originally Posted by jkv45

In their tests it cleared heavy deposits on valves and in the combustion chamber in one tank.

Perfect, that's what I need. Now, assuming that there's a lot of deposits on the valves, wouldn't that affect my clearance measurements? Like I said there was lots of oil and crap in the airbox so I'm sure some of that made it into the engine??

[jkv45]

Originally Posted by drychain

Perfect, that's what I need. Now, assuming that there's a lot of deposits on the valves, wouldn't that affect my clearance measurements? Like I said there was lots of oil and crap in the airbox so I'm sure some of that made it into the engine??

The deposits usually build up around the stem of the valve and don't affect clearances.

They restrict and disrupt intake flow, and in the combustion chamber can cause detonation.

[drychain]

Awesome, thanks!!! Should get those done tonight and i ordered parts for the front forks, wheel bearings and new pads.

Anybody know how i can tell if the rear shock is gone or do i need to ride it for that? like mentioned above its covered in oil from the airbox

[Ceeloo Yello]

Oh I forgot, you should check your cush drive as well.

[drychain]

Originally Posted by Ceeloo Yello

Oh I forgot, you should check your cush drive as well.

Thanks for that, mine are pretty loose. Do I get a new one or should I shim it?

[jkv45]

Originally Posted by drychain

Thanks for that, mine are pretty loose. Do I get a new one or should I shim it?

Shim it. Even if you bought new rubber pads it may still be overly loose.

https://faq.ninja250.org/wiki/How_to...the_cush_drive

[drychain]

Awesome, thanks!