Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet Electra & AVL => Topic started by: AVL Power! on April 01, 2013, 11:49:20 am

Title: Using UCE Pistons in AVL?
Post by: AVL Power! on April 01, 2013, 11:49:20 am
Hi all,

I was wondering that if we can plonk the UCE pistons in AVL engine bikes?  I have seen barrel, head swap till now and was thinking that once UCE gets the cafe racer, us AVL and CI riders might be able to upgrade their pistons to the new 535 pistons?

If the piston clearance is corrected, then can this piston swap job be done?

-Sanket
Title: Re: Using UCE Pistons in AVL?
Post by: ace.cafe on April 01, 2013, 01:14:40 pm
I have heard that the pistons from the AVL and UCE can be interchanged. I have not tried it to verify.
Title: Re: Using UCE Pistons in AVL?
Post by: AVL Power! on April 01, 2013, 02:18:08 pm
Ya the AVLs and UCE's have few things in common. I am counting big time on their 535. But again, the weight of the stock 535 piston is one important factor.

 
Title: Re: Using UCE Pistons in AVL?
Post by: motomataya on April 01, 2013, 02:47:24 pm
I understand they have a different deck height. If the info I have is correct, the AVL piston in the UCE gives a higher compression ratio. So you would be lowering it putting the UCE piston on the AVL.
Title: Re: Using UCE Pistons in AVL?
Post by: AVL Power! on April 01, 2013, 02:59:21 pm
It this because the UCE pistons don't have a flat top? I remember seeing few pics of UCE500 piston and remember them having a dished out part in the center or something like that.
Title: Re: Using UCE Pistons in AVL?
Post by: High On Octane on April 01, 2013, 03:30:52 pm
If they are dish top pistons, they should create higher compression.  Dish top pistons reduce the amount of air/space in the cylinder, thus compressing more air.  The biggest compression numbers are going to come from what the head itself can flow and produce.  Quality head work will produce bigger numbers than a piston itself can IMO.  Typically, a higher compression piston will increase performance, but it can only perform to the level the head will allow it to.

Scottie
Title: Re: Using UCE Pistons in AVL?
Post by: ace.cafe on April 01, 2013, 03:38:50 pm
It this because the UCE pistons don't have a flat top? I remember seeing few pics of UCE500 piston and remember them having a dished out part in the center or something like that.

It needs to be measured and compared for deck height, and the rest of the parameters.
Just because "it fits" and "it works" doesn't mean that it's going to "work good".

There's a lot more to piston design aside from "it fits".
Title: Re: Using UCE Pistons in AVL?
Post by: High On Octane on April 01, 2013, 03:40:56 pm
+1      Excellent point Ace!
Title: Re: Using UCE Pistons in AVL?
Post by: Kevin Mahoney on April 01, 2013, 06:19:42 pm
I second that emotion
Title: Re: Using UCE Pistons in AVL?
Post by: Michael Marsceill on April 01, 2013, 06:38:31 pm
I recall Scooter Bob swapping the piston in the  UCE for an AVL piston. The AVL is a flat top and the UCE is scooped out, so the compression ratio is indeed increased with that swap. I would expect just the opposite effect with an AVL piston in the UCE. I also recall that Scooter Bob went on to other things before really finishing the project. Try searching "AVL Piston" to bring up the old threads.
Title: Re: Using UCE Pistons in AVL?
Post by: GSS on April 04, 2013, 01:31:29 am
+1 on the ScooterBob recommendation.....he did put an AVL into a UCE.
Title: Re: Using UCE Pistons in AVL?
Post by: ScooterBob on April 04, 2013, 04:29:27 pm
It needs to be measured and compared for deck height, and the rest of the parameters.
Just because "it fits" and "it works" doesn't mean that it's going to "work good".

There's a lot more to piston design aside from "it fits".

I was born AT night - but not LAST night ...... It's cheap, simple, easy - and it works ... on ALL parameters. There are more than a few bikes out there running this piston with great success.