Need help from engine gurus

[dub c]

I'm looking to replace the inner bearing on my Novarossi Roma .25, I am unable to search for Roma bearings on Amain website. Now according to the exploded views on the novarossi website it shares the same bearings as several Nova engines. I will use the P5 as my model to search . And what I've found is 2 different out race sizes.

Many have an outer race size of 25.8mm and some have an outer race with a size of 25.4

This page kinda sums up my dilemma

http://www.amainhobbies.com/product...gine-Bearing-Novarossi-P5X-528X-TM928-C6-BB-1

I'm almost considering ordering one of each size, but I would rather not. I would rather not disable my engine to measure, I can't have the down time right now.

 

[Snook Man]

Novarossi 16800 is the rear for the Roma .25. It should be 14X25.8X6mm
Same bearing the .28’s I have use.
Preventative maintenance I presume?

 

[dub c]

I want to treat this engine right. I've got about 1.5 gallons through it now, seems like the right time to do it. We have a big Jconcepts sponsored race next weekend I'm looking forward to.

How do you feel about TKO ceramics?

 

[Snook Man]

I’ve used them in a few engines with good results/longevity.

 

[dub c]

Good, if I 2 day ship I will have them installed by next weekend.