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Finally dragged myself out of my hole to face the Falco and the replacement engine that never ran on the rear cylinder.

Lots of help from a few months ago - thanks for that everyone. Everything checked out - all services seemingly working fine. Shipped bike to Griff but just couldn't afford to keep it there for long so back it came with little insight in the few hours the guys had to look at it before I bottled out. It was noted though that this low mileage engine has been rebuilt with small valve heads. When I pulled the flywheel to check the key hadn't sheared it was clear some gorilla had been working on the engine, mashing up hex heads and omitting washers. Pretty sure the flywheel wasn't torqued right.

So back it came from Tamworth and into the back yard it went - goodbye summer.

But I had a look at it yesterday from the point of view that I knew nothing about this engine and had never been told it was running (I was, many times).

What do you make of the attached diagram wot I gone dun made this evening. Aprilia manuals are hard to interpret I find so some more hands on qualification would be appreciated.




I can't tell for sure whether this is right!

As for why someone rebuilt this alleged 10k engine...

I hate to think what damage was done... seems like a cam chain snapped.

What would go first - the chain or the valve?

This is an absolute headfuck, sounds like you have done everything the manual says, so WTF is going on....?
If a camchain had snapped ( very unlikely ) then Im fairly sure that would have completely dusted the whole motor in a big throwing bits out of the side of the lump way.
There seems to be a discrepancy in the whole alignment affair, maybe its down to crank sprocket/ motor built up out of wrong bits?
Why would anyone need to rebuild a lump at a claimed 10k ?
Cos they are a crook ?????

Well I ran out of daylight to get the rear cams back on track - I see why they make that alignment jiggy thing now...

It does make me wonder how long this engine's going to run for once I get it going. The trail's cold regarding its provenance... I was told it came from an RSV from Belfast dealership that was closing down - but what dealer would buy a bike that didn't run after a bodged rebuild? Could be a total pack of lies - doesn't really matter now as I've no comeback. Odd how willing the guy was to speak to me about it though - maybe he genuinely thought the engine was OK and just fibbed about it being a runner. I hate to think what's going to happen when I change the numbers with DVLA... if it comes up as stolen what might they do?

I guess I could be wrong and it's something else... but over on AP's Facebook page I was alerted to this: http://rsvr.net/backfiring-and-poor-idl ... 14078.html?

Same problem!

Don't know if it will help but I bought a bike which had a 'replacement' engine which had come out of a Futura and wouldn't run. I had similar issues in that I could not get it timed up correctly. I could set the crank at TDC but the timing marks on the (front) cams wouldn't line up correctly.

Turns out that the cam sprockets had been swapped because the heads were different. The sprockets on the different engines look the same but aren't! The bolt holes are in different places meaning that when you time it up you end up with the timing marks about 60 degrees out. Obviously wouldn't run.

Trouble is with your engine is you really aren't sure which bits they have used but this could be something to check.

A word of warning - I removed the tensioner and reset the timing so that it was 'right'. As i always do, I then turned the engine over by hand and the engine would lock up as piston met valves.

Ah yes.... we've been talking about this before - here and on apriliaforum.

Well those in the know (griff) confirmed early on that the bottom end is a big valve RSV, but running small valve heads. That's all I have to go on regarding what this engine's made of but there was no indication that there was going to be a problem.

His suggestion was that the flywheel had slipped on the crank, sending the timing way out of whack... the guy that flogged me the engine actually spoke to Griff so he was also under the assurance that this engine was a runner.

So I had it back as I was out of money, pulled the flywheel, which wasn't hard to do as it hadn't been torqued up properly following what was supposed to have been a sprag change - although that may just have been part of the rebuild.

Then I left it as my spirit and wallet was broken... but now I'm looking at again four months later my suspicions were raised as I cranked the engine over and saw that the ignition strokes were 60º apart... which clearly could work but the engine would shake itself to bits. Hence my diagram above to get confirmation.

I did get things into what looked like the right position last night but the inlet valves were hitting the piston so I'm one tooth out I reckon but couldn't be done with working bu the light of my iPhone - another go tonight!!

KitchenSync wrote:The Sage Continues

Regarding this one, you are rapidly turning into someone who knows his Onions.

Let's just hope it's not completely Stuffed.


Having had a quick read through, it sounds as though what your deducing may be plausible - here's to success when you get some better light on what you are doing.

Are you sure that cilinder 1 is front and there is no mistake there?
Long tome and lots of beer ago I did my engine (big valve single spark 09 heads) and there was something spooky.
Something like cilinder 1 or front is closest to the rear of the bike, not sure anymore but something strange.

Didnt write anything down and damn those beers again...

http://youtu.be/pKZfh9CX1ls

Well bugger me sideways with a torque wrench - the git runs !

Rear cylinder was 360° off it's stroke!

Would have spotted this months ago had the #%?!!%*€ the shipped it to me from Belfast not been so plausible with his assurances to both me AND Griff that he'd ridden the RSV donor before breaking it.

Kind of makes me wonder if any of the story behind this engine is true. Sprag was supposed to have been changed but it's clearly not been - the lobes are badly worn and the drive gear surface badly scored. Small valve heads on a big valve bottom end with mixed up fixings and no Loctite in sight for the rear cam gears.

One of the exhaust valves is at 12thou - do I need to attend to that urgently?

Anyways - thanks for all the encouragement guys and gals. Maybe I'll get one sunny day out before the end of the year!

Hurrah!!! Well done in finally getting to the bottom of it.

Farking hell, 360 degrees out. That has to be a record.

Good effort mate! this has to be one of the longest running issues ever, really pleased you got it sussed at last. Lets hope that you've identified the major issues, and everything else is smoother going!

Hi all.

well, guess hard work and commitment is the key. Good job :) Now ride the damn thing...

Great news at last!
You deserved it after all that work.

Duplicate deleted.

well that put pays to my motto.

"if at first you don't succeed....give up"

Well done that man