Quick Tip - Don't replace only the piston rings

Quick Tip - Don't replace only the piston rings - Replace the piston and the piston rings.

[dedsled]

These videos have been helping me understand my bikes and how to perform service work for the last 20 years. Thanks for the help!

[davidzelkowski]

I agree with you Jeff. I always install new piston and rings for the exact reasons you mention. I've seen the ring lands wear into a taper on the bottom.

[lboughto]

I agree just do the piston kit. I also always change the wrist pin bearing. Why doesn't the wrist pin bearings come with the piston kits? I forgot to order the wrist pin bearing on the last top end I did it delayed the build by a week waiting for the bearing to arrive. I was so mad at myself!

[elgringoec]

There once was a day when we used to pull the head and cylinder just to check on things. We'd inspect for scoring and measure for wear. If a piston and cylinder wall looked good and measured in spec, it'd go back in. We'd check ring end gap by placing the rings in the bore in their corresponding position at TDC - how that measurement compared to the specified gap range was our guide to how much wear they had left, if any. Of course visible signs of distress obviated the need for measurement when replacement was immediately indicated.

That was a lot less hassle when air cooled, no power valve mechanisms, easy to access fastener positioning, and room in the frame to work comfortably. 😉

[therandomman]

This makes a lot of sense! From now on I'm going to check the gap between the rings and the piston

[hammy]

Thank you, Jeff! I appreciate your advice on all these videos. Please keep them up.

[riadhch]

Thank you Jeff for sharing your experience
Your explanation is very reasonable

[Mikefngarage]

piston kits are fairly cheap. So better to replace the piston and rings. But if your broke and you just trying to keep your bike out for a season you can always do the cheap thing. I do piston kits as well.

[sid]

Thanks for the help. It makes sense to change the head too

[keystonemtb]

Thanks for sharing your knowledge, these videos are helpful to me and I am sure many others!

[brianricoh]

I agree, I never tear a bike down to just replace the rings

[lyndonewright]

I agree with you I change piston and rings and top end bearing and at 80 hours now back in the late 70, s early 80, s when I ran 1 ring piston I would change just the ring every other race that was riding 125, then keep up the good work

[bradl]

when younger, poorer, dumber(1990s)

my everything bike was a RM465 smoker, da torque, lol.

I changed rings 35 hours ish, piston at 100hours. rode that bike over 500 hours(I wasnt fast)

probably had 5 hours on new rings, 75 on the piston, bike ran like a top, climbing sand mtn, little Sahara, moving fast, piston skirt broke, lost the motor,

that set me back 3 years of riding, piston kits then were $40 ish, ☹

pre Slavens on youtube, nuts

love your tips, thanks for sharing

[korearoughterrainchannel]

Healthy piston surface keeps more oil and maintains the life of the cylinder.

[josephmontes]

Got low compression on my Yamaha blaster got new rings and piston i honed the cylinder had a few vertical lines but nothing to catch a nail I thought it would be good but compression was still low holds compression up to 60psi no leaking except when I can hear the air getting passed the rings

[ohdehhan]

Makes a lot of sense, thanks. Great shower analogy!

[striker]

Ok, here's a question. I rebuilt my 1975 GT750 with all new bottom and fresh Mitaka top end. It's a huge pain in the ass to tear the top end off this bike. Being a liquid-cooled triple, I was excited to run it, however, I had a crank seal issue, so back apart the bike came. I had ran the bike for maybe 30 minutes - 1 hour total off and on, chasing my tail with carb adjustments (hence the crank seal check). My pistons are already fairly scuffed, as well as the cylinder walls a bit. Nothing I could catch my finger nail on, so I honed the cylinders a touch with a ball hone and cleaned the pistons up. The pistons have very light scuffs on them. With such little time should I be replacing the pistons anyway? I'm already way over budget and time on this bike.

[johnsnyder]

Thanks for your videos…greatly appreciate!!

[daysinvegas]

Good afternoon, great video. I have a new 50cc 2 stroke that stopped running. The piston has a lot of blow-by and looks burnt. The rings are still moving freely however. The cross hatch marks are still visible inside the cylinder and there is no scuff marks. My question is - do I still need to hone out the cylinder when replacing the piston and rings even if no visible scuffing is seen?

[richardhartley]

Take a shower put your dirty cloths back on lol brilliant totally agree 👍🇬🇧