Planet Minis

LoudFastUgly

Well, I should've known when the P.O. said the clutch seemed to drag that there might be more wrong than just an adjustment as was suggested.

No troubles, new parts are on route.

Now, before I open the engine up, any guesses as to why the intake rocker arm is almost contacting the intake valve spring when the valve is closed? There's a fairly decent gap on the exhaust side, but for whatever reason mine is very and I mean very tight (can bearly properly adjust valve clearance) on the intake?

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firepower354

Small base circle 50 rocker on a big base circle cam, sounds like.

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LoudFastUgly

Tried to snap some pics, came out blurry. Intake and exhaust rocker's appear to be exactly the same. Is it possible that the valve seat could be so pounded that the valve is sitting higher than it should?

firepower354

Could be. Certain the right valves are in it? Can you measure the length of valve sticking out of the guide?

__________________
If it has my name on it I did it;)

FirepowerMinis.com
Custom FPM parts and engines.
Parts and service for all makes.
Honda Trail Bikes parts and accessories.
Pitster/Piranha/Thumpstar bikes, parts, engines and accessories.

arlindsay1992

If a valve job was done and the seat was cut it would put the valves up higher in the head.

LoudFastUgly

Anyone got a 'pat' process for tearing down the top end? Looking for input before i get myself in a bad spot:

To me, it seems it should be:

Head covers
Rockers
Cam sprocket
Head bolts
Head
intermediate cam chain pulley
cylinder

I've got a new timing chain and pulleys to install. I'm hoping rings only but lord knows everything else has been patched together...

Thanks,

Rob

tmas

Not sure what year you have but here is an on line manual from Honda50.com.
tmas

http://www.honda50.com/partslists/z50r-shop.pdf

arlindsay1992

cam cover
cam sprocket
head anchor bolt
cylinder anchor bolt
rocker cover
head
cylinder

LoudFastUgly

A Heinz 57. Beat to the last inch of it's life.

The frame is a K4, serial # on engine doesn't match the frame # but is the correct serial # range. It's got a 77 or 78 front end, and unless I miss my guess the tank is off of a K5. As previously mentioned, the clutch has been grenaded for some time (oil pump is clean!), bottom end and trans seems decent. Top end is missing at least one fin on each cover/component. I have a sinking feeling it'll need a new head (if so, I'll be hardcore on the hunt for CT70 bits, lost the last ebay auction).

It'll be a rider. The pic is the intended color scheme, RC30 would be to much I think.

Thanks for the link!

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LoudFastUgly

Nice! Coles notes on disassembly and FSM for rebuild, couldn't ask for more.

Thanks again!

mexicanyella

Regarding your serial numbers, if the engine numbers are in the correct range for that year, I think you can assume that's the engine the bike came with. My two K2s have the original engines in them, because I'm the second owner and the first owner is a friend of the family who never even rebuilt the original engines...and while both engines are in the correct range, neither one matches the frame number.

Good luck with your project, hope to see pics.

Z

Here's your engine ID:

Honda50.com Engine Vin Decoder

LoudFastUgly

Anyone got a spec for the length of the exhaust valve? Should it simply be the same as the intake?

Thanks!

LoudFastUgly

And the winner is...

Intake valve has nearly disappeared from the combustion chamber it's so buried into the head.

CT70 top end is en route.

Anybody interested in a good stock z50 jug and piston?

mexicanyella

I might be; what kind of shape is the bore in and how much are you asking for it?