Top end refreshment

[LesterPiglet]

When I got my 550 I'd only ever owned 2 strokes.
The first thing I did was fix the cam chain tensioner and regrind the valves. It's all simple enough with a Haynes manual.
Engine out/in is easy too. Lay the bike on it's side and lift the frame off it, reverse for installation.

[matthewmosse]

I also recall the haynes manual said you are unlikely to ever have to replace the hy vo chain - to be fair I've a few used ones about and someplace I had a new one and I couldn't tell the difference in wear between the new and a few of the used - there were one or 2 more worn examples in my collection.

[Bryanj]

Don't believe everything you read in a Haynes manual, I have come accross some real bad howlers!!! as to the Hy-Vo primary chain on the 400 its not too bad , on the 500 it wears badly and damages the main oil galleries and on the 550 the crankcases were different so the wear is not quite as bad so still there.

Same part for all 3 by the way (and a Kawasaki model I can't remember!!)

[bomber]

Thank you for encouragement.
I got my gasket set and ready now to tackle it.

Monday is the day (weather permitting), will drain oil and remove engine as suggested by Lester.
Will see what other surprises are there for me.

I just remembered that first gear occasionally was popping out to neutral...

Many thanks!

[matthewmosse]

I had a few engines where it poped out of 1st under load , both 500's - I'd sort it whilst you are in there f possible - on mine it took a year of commuting to get to the point where it was a royal pain, then it started doing it in 2nd too and I pulled the engine as I'm on a bit of a steep hill and it was getting 'not funny' going up the hill slipping the clutch in 3rd or poping out of gear and reving it's nutts off in 2nd every day.

[bomber]

I had a few engines where it poped out of 1st under load , both 500's - I'd sort it whilst you are in there f possible - on mine it took a year of commuting to get to the point where it was a royal pain, then it started doing it in 2nd too and I pulled the engine as I'm on a bit of a steep hill and it was getting 'not funny' going up the hill slipping the clutch in 3rd or poping out of gear and reving it's nutts off in 2nd every day.

Any suggestions what to look out for?

[matthewmosse]

I've not got around to look at mine yet, but selector fork wear or dogs and the selector drum are all suspect - think the drum is reputed to wear on the 500 but think that was revised on the 550.

[Bryanj]

I can second everything that Oddjob said and i worked on them for a living in the 70's

[bomber]

So, after few months I finally had a bit of time to get back to my bike.
I finally split the engine and i'm trying to assess what needs to be done, a part of washing sand away.

For the start it looks like there is no seal in between crankcases, should there be one??

[tom400f]

Jointing compound... no gasket if that's what you meant.

[bomber]

Tom there is nothing, I didn't expected gasket but there is no sign of a jointing compound, just a trace of light brown in one or two holes.
Oddjob, I haven't split gears yet but it all looks rather clean and there is no damage or wear a part of where bearing seat on case, I will try to post few more pictures tomorrow.

There seems to be a lot of play in primary chain, and with clocks reading 30k i'm going to replace it, but first have to free it, read somewhere about screwing one of the large engine mount bolts and slamming socket to pull it out, will try it tommorow.

I'm struggling to upload pictures, it seems that they are to big here is a link to them, i have to find a quick way to re sizing my snaps.
https://plus.google.com/photos/100803604774033940642/albums/6028232728034539713

[bomber]

Bomber I have managed to source some new gear selectors for the 500K, the middle one is very difficult to source these days and I've managed to find a few, I also have a new left hand fork along with some really good second hand ones which TBH look as good as the new one.
I have most of the gears NOS as well if it turns out you need to replace 1 or 2. Hope it's not one of the ones I'm missing as I spotted one on german E-Bay the other day and it was around £125 for just one gear.

When you split it and can check if there's any damage and if any of those parts are useful left me know as I don't expect the middle selector fork to not sell for long.

I had another closer look and i can't see any wear or damage a part of forks, but that is no way near as bad as I seen on forum.
I noticed that the fork wear is not even, and I wonder if I should be measuring the thinnest part of it rather than thicker.
I think that I'm either very lucky or blind...

Thanks a lot for the info, I couldn't get this far without this forum.

[bomber]

Looking for a hondabond ht, it seems I can only get it of ebay in USA
Anyone knows where to get it in UK?
Thanks

[JamesH]

http://www.ebay.co.uk/itm/370990844719

[bomber]

http://www.ebay.co.uk/itm/370990844719

Thanks!
this is the last bit of a puzzle! Almost ready to assembly the engine.