YZ250 spark plugs, and air filter question

[inotocracy]

I did a search but nothing came up for my bike, I also googled for some info but just wanted to confirm with the gurus since I lack the manual, and the maintenance manual I recently ordered wont be here before the weekend.

I want to replace my plugs (and air filter, liquids and what not) before the weekend but still unsure about the details. From what I gather the spark plug gap for a 1988 Yamaha YZ250 is .028, and NGK B8EGV spark plugs are compatible. Is this correct? Any spark plugs that would be better?

I've been told its good to replace my fluids also, so transmission fluid I assume? Also, in regards to the air filter, I figure ill buy a new one and from what I've read you are supposed to oil the lower part of the cone, is this correct? What kind of oil do I use? Anything else I should know?

I'd wait for my maintenance manual to arrive but I wanna go riding this weekend! :laugh:

 

[_JOE_]

Oh boy. You need that manual bad. I wouldn't mess with anything before you have the manual. Chances are you will mess it up more than help it. I doubt anyone will know the plug gap, but the number sounds good. Trans oil should be changed VERY frequently. The ENTIRE air filter should be oiled with AIR FILTER OIL ONLY. Coolant should be an annual change.

 

[docgonzo]

I have the same bike and usually use a NGK B8EG or B8ES. The B8EG is kind of hard to find outside of bike shops and I don't like paying their markup, some Napas carry them, but not all.

It sounds like you just bought this bike so definitely change the tranny oil. 10-40 is recomended so that's what I use. The capacity is cast near the fill hole, I believe it's 700cc's. I don't have a particular brand to recommend as I am still trying to find one that will make it shift better and am having no luck so far.

Same goes for the fork oil. You'll need the manual for that, it's not that hard but the manual will help. I think I used 5w in mine.

Before you ride it too much check the compression. I rode mine a couple of times after I bought before I did only to find it was way low and time for a rebuild.

 

[_JOE_]

Good advice. Docgonzo, have you tried Bel-ray Gearsaver? I had good luck with that stuff in my 2t trannies.

 

[inotocracy]

Wonderful tips, thank you! How do I go about checking the compression? I assume you're talking about the shocks? Thanks again!

 

[_JOE_]

Wonderful tips, thank you! How do I go about checking the compression? I assume you're talking about the shocks? Thanks again!

:bang:Umm, no. The engine.

 

[inotocracy]

lol shortly after I made that post I googled it and yeah I feel like an idiot. Forgive me, the last dirt bike I had I was 11 or 12 and I'm 25 now, so not much knowledge in this area.

 

[inotocracy]

Got a question regarding coolant, I've read that you should do 50% coolant and 50% distilled water.. but what kind of coolant should I use? Also, the coolant goes straight into the radiator in the front correct?

 

[IndyMX]

Have you ever operated a motorized vehicle before?

Yes, 50/50.. It goes into the radiator...

Use coolant made for a bike. Get it at a Bike Shop, just to be safe.

 

[inotocracy]

Yeah, I've ridden a motor vehicle before :whoa: I had a dirt bike when I was a kid.. I'd wait for my service manual to get here (ordered one yesterday) and just read through it but I'd like to go riding this weekend and it won't be here before then. Just wanted to do the regular/easy maintenance before I take it for a romp.

 

[docgonzo]

Don't worry about it, I've heard much worse. I had a guy looking at buying my RM400, he actually asked which levers were the clutch, brakes and shifter :ohmy: He had very little riding experience and I still had to talk him out of buying it :yikes:

While your tearing into it you might also want to check out the steering head bearings and shock linkage bearings. My steering head bearings were completely dry. That manual should help there too.

 

[inotocracy]

Thanks docgonzo, I actually do know how to ride one so I'm a step up from that guy! ;)

I feel a stupid asking so many basic questions but.. where else am I going to start? Once that book gets here I'll feel a little more confident working on the bike since I'll have a guide. My understanding is regular upkeep is required to keep a bike in good condition, and how am I supposed to know how well they maintained it, you know? I figure do the stuff I can gather on my own and the rest when I get more knowledgeable on the subject.

Is there something I can buy to lube that up? Could I spray standard WD-40 or is there a special lube? I noticed that the steering felt a tad stiff but I have nothing to compare it to (never had a 250), but I thought perhaps that was because I wasn't really riding the bike and just in a stagnant position. Could I ride it this weekend and wait for the manual to arrive then do it sometime next week? My checklist of things to do before I take it out this weekend:

Replace plugs (NGK B8EG, .028 gap)
Grease chain (guys have any recommendation for chain grease?)
Replace transmission oil (10-40, Bel-Ray if possible)
Replace coolant (50% coolant from a bike shop, 50% distilled water)
Replace air filter (and grease it using air filter grease, No-Toil I hear is good)
Get high octane gas and use 40:1 ratio with synthetic 2 stroke oil

Guess thats about it. Anything else you guys can recommend I do, please, feel free.

 

[IndyMX]

Didn't mean to slam you, but some of the questions you've asked are either common sense or could be learned quickly by searching the forums.

 

[inotocracy]

No worries.. but common sense to who exactly? Growing up with dirt bikes isn't all that common. Honestly, I have been searching around and haven't been finding the specifics I was looking for, I just want to be safe and not put a liquid, or some other part into my bike and then end up with a busted motor. I promise you'll rarely hear from me once I get my service manual, normally I'm a pretty self reliant guy-- I just don't have anyone who has experience in these areas for advice. Naturally I figured thats what a forum was for ;)

 

[IndyMX]

No worries.. but common sense to who exactly? Growing up with dirt bikes isn't all that common. Honestly, I have been searching around and haven't been finding the specifics I was looking for, I just want to be safe and not put a liquid, or some other part into my bike and then end up with a busted motor. I promise you'll rarely hear from me once I get my service manual, normally I'm a pretty self reliant guy-- I just don't have anyone who has experience in these areas for advice. Naturally I figured thats what a forum was for ;)

I meant common sense for someone who has at least a little experience with engines. :nener: