Send the crank and barrel off to PJME for a rebuild and hone.

The rest is a simple as following the Haynes manual.

Where in the midlands are you? I'll happily lend a hand if you're in Nottingham, I've rebuilt a few, and only had one explode prematurely, which was a mistake that I haven't made twice!

 

Lee William Threlfall has a very good reputation for rebuilds in the RS groups. Gavin Mills on the other hand, has a lot of hate going about him and it is said that he uses cheap parts and does poor work. Never dealt with the man himself, but he has a very bad reputation.

I doubt you can rebuild an engine and keep the stock piston. Barrel will propably be fine with a hone, but you'll need a new piston.

 

Cheers, both. I'm in Derby. Unfortunately time isn't ultimately on my side as my wife and I have recently had our first child hence the sending off bit. Much of the cosmetic work on the bike was done earlier in the year but we just couldn't get it to start and after a long thought, I want it done properly.

Lee

 

Well, if you can deliver it to me in Nottingham, I'll happily strip it down and give it back to you for getting the crank barrel and piston sorted by pjme, then once you've got them back I'll rebuild it.

It'll even be free, as this is my hobby rather than my job.

 

Cheers guys, I will have a look into it.

That's very kind, thanks for the offer, Sobriety. How much are we roughly talking for a full rebuild inc. parts? Are there any parts to replace that are a no brainer so to speak when rebuilding?

Thanks, both.
Lee

 

If it were me, I'd change all of the case bearings (mains, gearbox and balance shaft) while I had it open, I'd do all the seals too. And check clutch and gearbox shaft bearings, as they're pretty reliable, so don't need changing if they're not worn.

Depending on the cost, I'd be inclined to get it rebuilt with an Aprilia con rod and piston, just because. But that will be expensive. If you send it to PJME and ask their advice they'll fill you in on what's best in terms of price Vs reliability.

My last rebuild cost the best part of £700 iirc, but yours will be far cheaper as it's a maintenance rebuild, rather than a grenaded engine rebuild!

I'll see if I can work outs a parts list based on what you've said needs doing tomorrow.

 

Just done a quick ballpark price for the parts and work from PJME, you're looking at £350odd in parts and labour using a non-aprilia piston kit (I priced the mitaka, as the piston itself is ok, and PJME supply them with RIK rings, as the mitaka rings have a bad rep) or £500odd using genuine Aprilia bits in the top end.

I checked and the genuine Aprilia Conrod/big engine bearing/pin/washers are NLA

There may be ways to make it cheaper if you can fathom the Byzantine pricing on PJME's website, and there are certainly a lot of ways to make it more expensive by speccing things like posh pistons and con rods, or adding in a better power valve blade and housing...

 

You could use this conrod if you've got the bucks to spend.

http://mmgracingstore.com/en/engine-aprilia-rs125/140-italkit-double-forged-hand-finished-connecting-rod-aprilia-rs125.html?search_query=italkit+rod&results=9

And a Vertex piston kit or a Mitaka with Moto RRT rings as @sobriety said.