Your engine is only as good as the piston rings. If they suck, the engine sucks.
Through much blood, sweat and tears over the past 3 years I have determined the piston rings that come in the mainland china 50MM BBKs or any of the cheap kits for that matter are to be thrown in the trash, if you use them you are taking a HUGE gamble, your motor may turn out to be a smoker and have to be done over.
The options you have are to buy a HOCA piston and ring set from Parts For Scooters and just use the rings. I have had thousands of smoke free miles on these excellent Taiwanese piston rings
Several motors I have put Hoca rings in you can ride the piss out of em all day long and never use a drop of oil (the yellow bike in my profile pic now has 2000 miles on hoca rings)
China rings you might have 3 in 10 that will smoke like hell and 2 that smoke some and the rest are ok but you never know.
I hope this saves someone all the frustration I have been through. The mainland cheap china kits are fine except for the most important part, THE PISTON RINGS. Do yourself a favor and buy good rings. This is not my opinion, this is from direct experience having done at least 50 50mm ebay kits over the past 2-3 yrs. Never again will I use the piston rings that come in those kits ever. Hoca, RIK (Riken) or Wiseco from now on.
Oh and if you need top quality rings for your 52mm 90cc 139qmb use Racing Planet NK100.86 those are Riken (Japan)
Last Edit: Aug 21, 2013 16:09:44 GMT -5 by Deleted
The main reason I posted that was for the filing information and especially whats in 'Illustration 3' about oil ring expander overlay. That is VERY important. If that is done incorrectly it WILL burn oil. Several oil burners I have done myself in the early days of working on scooters and some that owners tried to do themselves that I did over recently for them, the problem was exactly that. Incorrect oil rail expander butts.
Last Edit: Aug 29, 2013 13:25:53 GMT -5 by Deleted
Senna1Rossi: Ah, gotcha! Thanks, Fox. Does everyone see the Shoutbox, or just the people who you choose?
Feb 16, 2016 12:39:35 GMT -5
Fox: Anyone who is logged in can see it but it's down at the bottom so most have either chosen to ignore it or haven't discovered it yet.
Feb 16, 2016 18:42:39 GMT -5
Deleted: Wow, I just found this. I feel smart now, ha ha.
Feb 27, 2016 19:24:24 GMT -5
Silar: Ahh.. New feature for a new riding season! YAY!
Mar 16, 2016 17:12:34 GMT -5
Silar: Apparently this still is not being used much. hmm..
Mar 17, 2016 13:55:04 GMT -5
180°off: Anyone want to buy a Yamaha 2t that needs a complete rebuild?
Mar 27, 2016 16:00:19 GMT -5
larryhobman: What is the leanest jet size you would try on a 47mm setup, 60cc stock head with a A9 cam
Apr 2, 2016 20:17:30 GMT -5
Senna1Rossi: Thanks renagade281!
May 23, 2016 14:59:12 GMT -5
Fox: I don't really know how to say this but straight. I am Dave's Girlfriend Kellilee and bluntly and VERY SADLY he passed away early Tuesday morning. I know he would want ya all to know this. Thank You Brent for befriending my love he was very happy on here!
Jun 18, 2016 16:26:04 GMT -5
Fox: www.gofundme.com/29mgf6b8 I hope it is ok to pass on his gofundme page link. If not you will un-post it I'm sure. Thanks again all!!
Jun 18, 2016 16:31:18 GMT -5