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Serdna
20-04-13, 09:29 AM
****Videos now added****

Good morning. Today I should be putting the last few bits on my SV after a pretty much full strip and rebuild this winter and going out to ride it. Unfortunately I'm not. It seems instead i have a massive PITA problem that will take time and money to fix.

The bike: 2001 SV650.

The engine:
A second hand engine from 1999 i think. It had MOT's to prove a low mileage of 4000, but who knows? After doing a cam swap I'm a bit dubious. Its had silicon gasket on gasket mating surfaces(valve covers,clutch cover and alternator cover. I didn't open anything else), a rounded timing inspection cap and the cylinder head cover had two damaged threads (in the camshaft holders) on the front cylinder. Also the rear cylinder hisses as you turn the engine (spark plugs in, carbs/exhast off) as if there is air escaping, the front doesn't seem to. I guess i can investigate that better when I drop the engine out.

However even with those setbacks I sorted out all the problem bolts/threads and got the engine running (before i put on chain and sprockets) the bike ran sweet as a nut. It warmed up for 25min on idle(IN NEUTRAL (this is important to show it was working at this point), no strange noises, the new engine sounded very good. I could push the bike around in Neutral no problems.

Fast forward a couple of weeks. I'm throwing this out there as a possible cause to the problem but I'm not convinced. I don't have a good enough stand to lift the front end so because there was no bodywork on the bike I laid it on its left side to remove the forks and change the head bearings. I removed the races from the frame also which took a few hard knocks.

So the problem:

I got the bike up on the paddock stand. (The bike is now almost fully complete. I have to screw down tank and seat and tidy wiring at the front of the bike and add a headlight.) With the engine off, clutch out. I turn the wheel backwards and forwards with my right hand and play with the gears with my left. I can find first ok clicks to 2nd/3rd/4th/5th/6th and back down with wiggling of the wheel. But i can barely find neutral (remember clutch not involved here, engine off). When i do find neutral when i turn the wheel the gearbox is making a loud clicking/clacking noise (much like an RS125). I can normally get around a 1/4 to 1/2 a turn of the wheel before the bike goes to first gear. THE BIKE WILL NOT STAY IN NEUTRAL. I try this again and again to the same end. I am sure I am looking for the neutral between 1st and 2nd. I checked and double checked that, its not a false neutral.

So my optimistic theory was, engine not running = gearbox not working as designed = root cause of the problem. So side stand up, clutch in, choke on, thumb the starter. She starts fine, running ok. But there is a terrible clatter coming from the gearbox. If i try to find neutral i get the same result as above^^^ but it just jumps sooner. (clutch in all this time). Remembering the bike is on a paddock stand and the wheel is free to spin, I select first gear, carefully let the clutch out and the bike stalls. Start it up, try 2nd this time, again it stalls. with third the bike didn't stall and the wheel turned but there was a horrible wining noise of gearbox parts rubbing together in the wrong way.

My diagnosis is the gearbox is fooked and will need a complete strip down to inspect/replace parts.

Is there any way these symptoms could be connected to the shift star mechanism going out of place or even a clutch or starter clutch problem?

What do I need to buy to do this job? Will a full gasket set suffice + anything i find whilst stripping down? What am i likely to need to replace gearbox or otherwise?

Thanks in advance with your advice. If handy anyone is passing through West Oxfordshire today and thinks they might be able to help with diagnoses it would be much appreciated. I will ply you with refreshments and chatter.

Serdna
20-04-13, 11:28 AM
4 Videos will speak a million words. I'm uploading to youtube at the moment so will post up here in a couple of hours when they are done.

Serdna
20-04-13, 11:57 AM
The first, but not particularly helpful Video. The next two show a problem very clearly.

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Serdna
20-04-13, 01:13 PM
A more informative video maybe. I said side stand, I meant paddock stand. At the end i didn't find neutral, i just stopped the video. Next video is of the bike running.

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Serdna
20-04-13, 02:03 PM
This is a video of the bike running. Last night the wheel span with the bike in gear, clutch in but stalled when i let the clutch out. Today the wheel didnt spin in gear with the clutch in but it did spin in first gear as i let the clutch out. As you see at the end of the video it got really ugly really fast so i pulled the clutch in and switched it off.

New theory. Myself (i very much doubt it) or a previous owner (the engine had been spannered on before) dropped something into the engine. It was happily sittings where it was until i turned the bike on its side and this moved it to the gearbox, causing this problem.

And you are all out riding today!:smt076

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Serdna
20-04-13, 02:24 PM
And the final video. Funny smell. It could be coolant on the exhaust maybe. I did get it a bit all over the place yesterday topping up the rad. But the engine wasn't running long at all as you can see, and both times i noticed it, today and last night were just after I had tried to let the clutch out in gear. It smelt a bit too plasticy to be clutch but I'm not sure.

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Serdna
21-04-13, 09:16 AM
Has anyone got any suggestions? Otherwise i will drop the engine out today, give it another good wash and prepare it so i can strip it down over the week.

Serdna
21-04-13, 03:58 PM
:smt105I think I've been a TW*T. SH pointed it out it should have prompted me to check that first before stripping the gear change mechanism. The neutral between 5&6. Is the linkage connected upside down in vid 1? Or better still post a pic of correct curvy linkage.

yorkie_chris
21-04-13, 04:33 PM
Linkage on shift shaft should point upwards

Serdna
22-04-13, 04:40 AM
Personally i think you lot are the idiots for assuming i was clever enough to get the linkage the right way round. :p

Oh the embarrassment! Fixed now. Sunny weekend wasted. Live and learn!

yorkie_chris
22-04-13, 07:54 AM
I've done the same thing before myself... took me a couple of miles of "going WTF?!" to realise that it was all backwards!

Serdna
22-04-13, 11:22 AM
Lol well a bit better than me. I got the clutch off and had the shift-star in my hands for 15min before i twigged. I was like why is neutral between 5th and 6th? Then it dawned on me. oh well at least it was a cheap easy fix in the end, and I rode my SV to work today. :)