oneTRICKYZ250 My Ride Posted November 20, 2015 (edited) I'm getting Ready to installed a Wiseco piston kit (std bore) & Pro X gasket set in my 2015 YZ 250 2 smoke,the bike has about 20-25 hours on her & I want to keep Everything Fresh, NOW I been out of the loop for 28 years, But back in the Day we never Honed our Cylinders just slammed in a New Rings &/or Piston, Since the Hours are so low on my 2 Smoke the Cylinder should be in Good shape in theory I'll know more once I tear her Down, my Question is Do any of you Guys Hone the cylinder everytime you Freshen up or just if you feel it needs it? Sorry as I said just got Back into MX last April, I got the 2 smoke in July before that I was Riding my 2011 YZ 250F Which I plan to freshen up Before Spring as well, thanks for any positive advice. snarky Remarks will be ignored/ Edited November 20, 2015 by HURRICANE HUBBARD Share this post Link to post Share on other sites
William1 My Rides (2) Posted November 20, 2015 Clean with a scotchbrite, wash. Wipe with a clean rag and atf. Repeat until the clean rag stays clean. Wash again and assemble. 3 Share this post Link to post Share on other sites
justaskmenicley My Ride Posted November 20, 2015 It all depends on the condition of the cylinder. If there is nothing you can feel with you finger nail it will be fine. 1 Share this post Link to post Share on other sites
MJP68 My Rides (2) Posted November 20, 2015 (edited) Clean with a scotchbrite, wash. Wipe with a clean rag and atf. Repeat until the clean rag stays clean. Wash again and assemble. Similar process for me as well. The Scotchbrite helps deglaze the plating on the cyl. Edited November 20, 2015 by MJP68 Share this post Link to post Share on other sites
orangyktmthing Posted November 20, 2015 I run a light hone if the plating looks fine. A lot quicker than sitting with a scotchbrite pad, but hey, to each their own. Share this post Link to post Share on other sites
yz250474 My Rides (2) Posted November 20, 2015 (edited) guy at my local machine shop said my cylinder just needed a "hone" this is what the piston looked like after 8 tanks. I'm going to send it to Ken Oconner for a replate. Edited November 20, 2015 by yz250474 Share this post Link to post Share on other sites
oneTRICKYZ250 My Ride Posted November 20, 2015 guy at my local machine shop said my cylinder just needed a "hone" this is what the piston looked like after 8 tanks. I'm going to send it to Ken Oconner for a replate. WOW, was that after you had the cylinder Honed? Share this post Link to post Share on other sites
spiderwebb Posted November 20, 2015 The above photo can tell you about your jetting as you know. The excessive carbon build up resulted in the lower ring getting stuck and not doing its job. That's why you see all that blowby. Jetting could too rich or timing is too retarded or its cheap oil..? Write down the jetting and check to see it right. Check your squish Check your new piston rings gaps are to spec Check timing Share this post Link to post Share on other sites
oneTRICKYZ250 My Ride Posted November 20, 2015 scotch bright by 3M sounds like the best option thus far I do know that After the Cylinder is deglazed it should have a dull "scratched" appearance. Share this post Link to post Share on other sites
Shawn250 Posted November 20, 2015 Dont hone it , use scotch brite pad as per William above. If should never need a hone near it , when its worn it needs replating. 1 Share this post Link to post Share on other sites
oneTRICKYZ250 My Ride Posted November 20, 2015 Dont hone it , use scotch brite pad as per William above. If should never need a hone near it , when its worn it needs replating. yeah, that's kinda what I've been finding out thru reseach, this Dude said the samething--> 1 Share this post Link to post Share on other sites
yz250474 My Rides (2) Posted November 21, 2015 WOW, was that after you had the cylinder Honed? Yes. I think the crank seal on the clutch side was letting oil in... not sure if it would cause the piston to look like that. Share this post Link to post Share on other sites
yz250474 My Rides (2) Posted November 21, 2015 (edited) the manual says nothing about honin yeah, that's kinda what I've been finding out thru reseach, this Dude said the samething--> if I remember correctly that's what Yamaha says in the manual.. I didn't know that til after tho. Edited November 21, 2015 by yz250474 Share this post Link to post Share on other sites
oneTRICKYZ250 My Ride Posted November 21, 2015 the manual says nothing about honin if I remember correctly that's what Yamaha says in the manual.. I didn't know that til after tho. a Local Yamaha Dealer is still telling me Honing don't Hurt Nikasil cylinders..BULLSH*t! THIS ISN'T 1976 all the crap isn't necessary because all that ole skool stuff was cast iron, like the older machinist Dude said in the Video I Posted Less is more, I trust that opinion. Share this post Link to post Share on other sites
oneTRICKYZ250 My Ride Posted November 21, 2015 Yes. I think the crank seal on the clutch side was letting oil in... not sure if it would cause the piston to look like that. I think you had piston slap causing it due to the Honing, just my opinion now that I'm up to date on this newer Engine stuff. Share this post Link to post Share on other sites
yz250474 My Rides (2) Posted November 21, 2015 I think you had piston slap causing it due to the Honing, just my opinion now that I'm up to date on this newer Engine stuff. the engine was making a lot of noise when I bought it, which was why I took it apart to begin with.... anyway I got my new piston today I decided to try pro x, I hear nothing but good but not much. I have the Wiseco that came out the bike when I bought it to compare it to.... I can see some differences... 1. the ring position 2. the intake port, the pro x piston has an angle on it... the Wiseco is straight. (hard to explain, I will try to get a good picture) maybe someone can explain? 3. the dome........... Im no expert at all but from looking at it it seems the domes are a bit different... wouldn't that change your squish? in other words, would it be a waste to have your head cut to set squish with certain piston if you are going to change to a different brand? Share this post Link to post Share on other sites
yz250474 My Rides (2) Posted November 21, 2015 (edited) a Local Yamaha Dealer is still telling me Honing don't Hurt Nikasil cylinders..BULLSH*t! THIS ISN'T 1976 all the crap isn't necessary because all that ole skool stuff was cast iron, like the older machinist Dude said in the Video I Posted Less is more, I trust that opinion. yeah they dont know sqit. I took my cylinder there to see what they said caused it, he said I could of saved the cylinder if I installed new rings earlier, to bore it out and buy a piston to fit..... I just walked away... https://www.youtube.com/watch?v=IPnsouKN3Gk I just knew it didn't sound right. I took it to this Yamaha dealer after he honed it to have them measure it, they said run a standard piston which I did, the piston I showed you was a new one. Edited November 21, 2015 by yz250474 Share this post Link to post Share on other sites
markmc2 My Rides (2) Posted November 21, 2015 Sounds nasty Share this post Link to post Share on other sites
THUMPERRRR My Ride Posted November 21, 2015 Sounds nasty indeed... Share this post Link to post Share on other sites
Kinger317 Posted November 21, 2015 Next time you have the right side case off grab the bolt on the end of the crank that holds the gears on. Try to move/wiggle it up and down. Any movement at all and you should do bearings, that is usually what causes a seal to go bad. My bike sounded like yours and when I did crank bearings it was very quiet. Share this post Link to post Share on other sites