Bridgestone Motorcycle Parts Discussion Board
Bridgestone Tech Talk => Tips from Richard => Topic started by: Richard Clark BS parts on February 26, 2009, 05:17:40 PM
-
Bridgestone 90cc and 175cc Piston rings.
Piston rings for the 90 and 175cc Bridgestones have been long confused. In the past if you installed
wrong piston rings you would waste a cylinder and have to get a new one, no problem except for the cost.
Today with new cylinders almost being gone it is now a BIG problem.
There are two styles of 90cc cylinders: Cast iron and cast aluminum. All BS 175's are cast aluminum
Rings and pistons for cast aluminum 90cc cylinders and 175cc rings and pistons are fully interchangeable.
Rings made for cast iron cylinders are NOT to be used in Alum cylinders for any reason, yes they will
fit, and that is the problem, many people have supplied rings made for cast iron cylinders to folks to use
in cast iron cylinders. The problem is rings made for cast iron cylinders will wear out the cast aluminum
cylinders real FAST.
What is the difference in rings for cast iron and cast aluminum cylinders?
Rings for cast iron cylinders, are chrome plated cast iron.
Rings for cast aluminum cylinders are plain cast iron.
Reason is cast iron cylinders need chrome plated rings, and cast aluminum cylinders MUST have plain cast iron rings.
Further confusion is that the 90cc cast iron cylinders can be bored to oversize, in which Bridgestone did
supply oversize pistons and rings for these cast iron cylinders.
The SR 175, although it is a aluminum cylinder, the bore size is a bit smaller, so these will not work
in any other Bridgestone,
In the end it is pretty simple: If you have a cast aluminum 90cc cylinder or a 175 then your rings
need to be cast iron with NO chrome plating, correct part number is 1305-5010, but many rings have been
switched in boxes, so be careful. We recently bought a large inventory of new BS parts, we got many boxes of rings
marked 1305-5010 , but these boxes has the wrong rings switched inside.
Hope this helps a bit
Thanks
Richard Clark
Introducing new parts items available NOW.
50-60 All sport
90cc All models including 90 sport
100cc All models, including air cleaner rubber
60 cc Chibi, Tora and 100cc Taka.
175-200cc All models, including air cleaner rubber
350cc All models
Above listed rubber carburetor caps now available.
New supply of original 175-200 Fuel petcocks available now.
Thanks
Richard Clark
I have the worlds largest inventory of new and reproduction
Bridgestone motorcycle parts. Let me know your other needs.
Terms:
We accept Visa. Mastercard Credit Cards, along with Money Orders
For your protection we only accept credit cards by telephone authorization.
Thanks
-------------------------------------------------------------------------------
Richard Clark
4846 Quarry Rd
New Albany IN 47150
812-944-1643 8am -6pm EST Only Weekdays
NOTE: EXTENDED HOURS
PLEASE NOTE: THE ABOVE ADDRESS IS FOR MAIL USE ONLY,
I keep no machines or parts at the above address. Also there
are no business hours at the above address.
Visit my BRIDGESTONE MOTORCYCLE website
http://www.bridgestonemotorcycleparts.com/ (http://www.bridgestonemotorcycleparts.com/)