R5B piston styles

[Greaser Greg]

Are there two different, or more styles of stock r5 Pistons? I don't know how to reduce file size to post pics. The Pistons I received from eBay are different in that the crown of the piston is recessed to expose more of the first ring land, and the lands are both farther up. The ring will be exposed to combustion with just enough piston to hold it in the groove. Is this the right piston?  Same in other aspects.

[teazer]

That would be a piston that has a Dykes top ring.  They are an L shaped ring that comes up the side of teh piston to provide better port coverage/sealing/timing.  They fell out of favor for reason of cost of manufacture and higher revs require lighter rings, so they are less common today.

[Greaser Greg]

Well crap I bought some.   

[SoCal250]

If you need to find rings for your pistons, I have this info in my notes

RD350 piston rings - Dykes style ring set
360-11610-02-00 STD
360-11610-12-00 1st over
360-11610-22-00 2nd over
360-11610-32-00 3rd over
360-11610-42-00 4th over

[Greaser Greg]

 :vroom:Thank you, that's very helpful.

[SoCal250]

:vroom:Thank you, that's very helpful.

Since you brought this up I'll update my personal notes and add the info the the Tech Library for future reference. I'm sure others will have the same question. In fact, while looking at rings for you on Ebay I noticed a lot of sellers offering mismatched pistons and ring sets in their auctions.  You could even see in the photo that the piston was Dykes and the rings were keystone.

[Greaser Greg]

That would be a piston that has a Dykes top ring.  They are an L shaped ring that comes up the side of teh piston to provide better port coverage/sealing/timing.  They fell out of favor for reason of cost of manufacture and higher revs require lighter rings, so they are less common today.

Thanks, teaser.
So, they will work fine in a stock motor as long as I don't over-rev too much, correct?

[Greaser Greg]

:vroom:Thank you, that's very helpful.

Since you brought this up I'll update my personal notes and add the info the the Tech Library for future reference. I'm sure others will have the same question. In fact, while looking at rings for you on Ebay I noticed a lot of sellers offering mismatched pistons and ring sets in their auctions.  You could even see in the photo that the piston was Dykes and the rings were keystone.

Thanks, again.  I noticed that also. Maybe I'll send 'me a note about it for the next newbie.

[teazer]

If you have them, run them.  Wiseco used to put L shaped Dykes rings on many of their 2 stroke pistons.  nothing wrong with them.

[Greaser Greg]

Sweet! I'm waiting for delivery of rings to go on them, and to hear about the crank I sent in for rebuild, oh yeah, and to get the cases clean, and...and....
Thanks

[bracket maker]

I don't understand. why not run shee piston kits? why go retro. dykes and keystone have been phased out for a reason. no modern bikes run them.

[Jspooner]

I don't understand. why not run shee piston kits? why go retro. dykes and keystone have been phased out for a reason. no modern bikes run them.

By "shee' i assume you mean Banshee, this isn't an RD, its an R5 - piston port.

[Barrie]

So , early two strokes  can run modern type pistons, wiseco pistons change regularly ,early Kawasaki pistons were Dyke ring type ,but now run keystone configurations  , some thick ,some thin section.

[bracket maker]

I don't understand. why not run shee piston kits? why go retro. dykes and keystone have been phased out for a reason. no modern bikes run them.

By "shee' i assume you mean Banshee, this isn't an RD, its an R5 - piston port.

got it. so it might be a good idea to get the whole top end kit.

[m in sc]

if you can find a full set of r5 stuff, yeah. the dykes rings run really well, however they will pack with carbon when running really old style or dirty burning oil. at the time, thats the reason they quit running them. Im sure cost was a factor as well, and then with higher revving motors they probably wear out faster due to weight, etc. Ive run them, with modern oils they work great and actually seal better. (larger contact area and the gasses push the top ring out to help seat).   

I think wossner made new r5 pistons at one time with keystone rings.  its basically the same as a banshee style piston with no intake hole.