Big problem this time - bike sounds like a sewing machine and no power

[xwhatsit]

OK, cheers Ixion. The bike is on the centre stand, and isn't going anywhere, so hopefully it'll be easy enough to retrieve.

I thought they checked the engine number at WOF? I know when I did a VIN check on the internet before I bought the bike the engine number was listed there, so it seems to be officially recorded; will it not be a problem the two numbers don't match?

[Ixion]

No, they record the engine number, but people often swap engines. It's the frame number that "identifies" the bike. Never had anyone check engine number at a WoF.

[xwhatsit]

Oh brilliant. Perhaps if lb99 has an engine for me, for a price that won't have me dropping out of uni, that could be an option

[FROSTY:Me]

ya silly bugger---why in gods name diddnt ya wheel the bike over the road to the caryard like i told ya to?--
i had my toolbox out back

yea that was me in the green shirt-came over to help ya out in belmont

[xwhatsit]

Hahahah! You know I had a sneaking suspicion you were a KBer, normal people usually aren't so friendly, and I saw you had a bike...

No well after I rang the AA I thought they'd be about 10-20 minutes or something, and I told them I'd meet them down on the corner. Didn't know I'd be waiting near 2 hours...

[lb99]

I'll do my best for ya, usually a good motor for anything will fetch a premium, your bottom end is most likely still ok ( fingers crossed) and maybe the head is too, its a pity I'm not in scabby old Auckland or we'd have the bike in my garage by now.; post a list and pics an we'll go from there

chin up dude.

[xwhatsit]

I'll do my best for ya, usually a good motor for anything will fetch a premium, your bottom end is most likely still ok ( fingers crossed) and maybe the head is too, its a pity I'm not in scabby old Auckland or we'd have the bike in my garage by now.; post a list and pics an we'll go from there

chin up dude.

Cheers mate! I think in fact you're rather glad you're not in `scabby old Auckland' if you ask me .

Good news first. Bottom end seems fine, rotates nice and smoothly, the only damage I can see is a couple of marks on the piston where the intake valves hit, but I think that all it did was cut through the thick carbon layer on it ^_^.

Alright, here's the photos. I've omitted a couple, notably of the valve cover, as although there is a gouge or two on it, it's not on the bearings and looks to be quite minor (it's in the cam chain tunnel, well if you can call it that in the valve cover).

The pictures:

1. Piston, with two little marks from intake valves. Is it OK? I think so, but what do the clueful people think?
2. Cam sprocket, camshaft. Camshaft is definitely toast lol. Bit of it still attached to cam sprocket
3. Sprocket seems OK, apart from the now elliptical bolt hole. Correct me if I'm wrong, but it's not seaworthy, is it
4. My $200, 35km-old cylinder head. Bearing surfaces look bad, but my biggest worry is the bearing where the tacho drive fits; see how one edge is bent? The camshaft doesn't want to fit in there anymore. Can this be repaired, or is it toast?
5. The head from the top. Is it going in the bin?
6. Heheh now those are bent . I'm glad it was the intake valves; I have a pair from the old head that haven't been subject to any abuse, at least while I've had them. Should be easy enough to change; will the oil seals need to be changed too? (BTW, please ignore the large single cat hair on the valves in this shot...)

Alright, there we are. So, all in all, it could be worse. I'll need a new camshaft, cam chain, sprocket (unless that elliptical hole is somehow deemed acceptable) at least. I'm very much hoping the head won't need replacement, but it's looking a bit the worse for wear. I noticed you said, Ixion, that you can sometimes remachine the bearing surfaces, but is mine too far gone? (Point of interest, in the Haynes manual it says that many owners would take their heads to have needle roller bearings installed in them). But the bottom end looks sweet, thank god for that!

[FROSTY:Me]

Dude --The way it was locked up solid I'd like to see what the cam chain tensioners look like -I have a sneaking suspicion one has broken,not been fitted propperly--or backed off

[xwhatsit]

Dude --The way it was locked up solid I'd like to see what the cam chain tensioners look like -I have a sneaking suspicion one has broken,not been fitted propperly--or backed off

Here they are... they look fine to me, but then again I'm not the brightest tool in the shed. The spring-loaded tensioner has wear on it, but then again it's supposed to; Mr Haynes says nothing else on the matter but `using a cam chain tensioner until the metal shows through is bad practice'. Lol. The cam chain guide looks pretty mint too.

BTW: that's the best shot I can get of the chain tensioner, as I can't get the bastard out. I took the upper and lower tensioner bolts out, and it's free to move forward and back in the chain tunnel, but there seems to be some sort of pin or something holding it in at the bottom, and it just swivels on that but won't come out.

[lb99]

you are a machine dude.

but seriously, that bearing looks rooted, but I have seen them worse, if you clean up that outer bearing edge carefully with a file, you might be able to save a few bucks in the short term, its hard to tell from the photo, but if it was me (bush mechanics) I'd give it a go, shit like this never stopped Bert Munro, that cam is fucked, I'd say that one of your sprocket bolts came out and jammed on the inside of the head(big curved scar), but if the sprocket is still flat then I'd give that a go too, the bolts only stop the sprocket from falling off, its also held on by the shoulder that it sits on on the cam, but saying that a replacement cam would probably come with one anyway, valve stem seals are easy to replace, but you fuck em when you remove them, but if you can't get them cheaply from honda, take it to an engine reconditioner, because sometimes car ones can be the same.
is your head warped? sit it on a flat surface and see if it rocks, that may be why the cam won't fit, mind you it wouldnt surprise me if that cam is bent, cause it took a hell of a knock
Your best bet is for a new head, cam, chain and a gasket set, but that means dollars$$$$$

cheers

[xwhatsit]

OK, thanks. Would you say that the valve seals will need to be replaced? Do they bend?

Alright, I'll check out if the head will sit flat; will have to get those studs out somehow first. Hahah I might give it a go too, to clean up the head, pending disapproval from other KBers? Lol.

Yep the sprocket is still flat, so I can keep it? Woot.

Gasket set, that's a new one. My head gasket, I think it's metal, if I cleaned all the grime off it. It seems very solid, but is it still recommended to replace? The other question re: gaskets is that I just saw a new thread come up last night about a guy asking how easy it was to replace his rocker cover gasket; I posted a useless reply in the order of `Bikes have rocker cover gaskets? '. So am I supposed to have a gasket inbetween the head and the valve cover? The first time I opened it up, I noticed there was some of that crispy black stuff that you smear on and it hardens up. Missing a gasket if I'm supposed to have one would explain oil leaks...

[Ixion]

Valve seals don't bend but they do wear. Most bikes have a rocker cover gasket, but not all. And use of one of the "plastic gasket" products is common. And usually works OK

I *think* the head could be cleaned up. But you'd need to do it yourself, no professional mechanic would touch it. A job for that well known engineering firm Bodger & Bashit.

I'd be a little hesitant about that cam sprocket. The danger is that the bolt hole is ovalled. That could allow the sproket to rack about on the other bolt if there is any slack between the sprocket inner face and the camshaft boss, which could cause the bolt(s) to lossen off, and here we go again.

But, if you can't get another one cheap, it's not way out of line (they are still available new! About $US35 . I'm impressed).

I agree with Mr lb99's assessment of cause. The "missing" camshaft sprocket bolt came out. That then allowed the came sprocket to twist and flex, snapping the remaining lug and flicking the chain off. Why the bolt came out ? Dunno. No Loctite. Not torqued, too loose. or too tight and stripped.

It's hard to tell without actually seeing it, how bad that scoring on the centre bearing is. The damage on the outer bearing surface is not such a biggie, it can be cleaned up, thats a ball race sits there , you just have to keep it in place.

Toolmakers file, scraper, small punch , little light hammer and LOTS of patience.

[xwhatsit]

Schweet . OK I'll look for a new cam sprocket as well, if it might cause something similar to happen again haha.

The missing camshaft bolt, before it fell into the sump when I was pulling it out (it was rather finely balanced in a spot I couldn't get it out), looked like it was covered in metal. I.e. it was smooth, instead of threaded, and wider than usual. So I wonder if it pulled out the camshaft thread? So hmm at any rate, I'm definitely going to borrow a torque wrench and get some loctite when I put it all back together. Heheh won't forget to do that in the future, now, will I!

Query regarding the outer beraing, you said a ball race sits in the groove, my camshaft doesn't have any ball bearings, is it supposed to? I think the very outer groove has something to do with the tacho drive, I don't think it locks into it, but maybe it's like a gap for oil or something. Don't quite remember how it all goes together, will have to have a closer look.

Heheh, I can put up with `lots of patience' bit.

Thanks guys.

P.S. If nothing else, I've managed to boost my post count rather nicely

[scumdog]

I like your attitude dude, you'll go a long way in this world!

None of this namby-pamby wringing of hands and snivelling about how hard life has been on you.

[xwhatsit]

Hahah, thanks, I think, unless you were being sarcastic!

I can do the whinging if you like, `no money, no bike, not getting any from the girlfriend now I'm poor and not a bad biker dude :'('

Nah well I fucked up, I've got to fix it now, and it's a lot easier to do when you've got the collective brains and generous spirits of KB behind you!