With the valve removed start with the coarse paste, and coat the valve or valve seat with a small amount of paste. Insert the valve back into the head and push the rod and suction cup tool onto the face of the valve. Then turn the rod (and valve) clockwise and counterclockwise so the valve and seat are rubbing together. Every few turns you should lift the valve off the seat and then push back down again. Clean away the valve grinding paste, and check the seat as well as the valve. There should be a dull grey line around the valve and the seat, this is where the valve and seat are meeting. You need to keep grinding untill this grey line is uniform all away around and is about 1.5mm in width. Then just repeat with the fine paste to finish off. Clean all surfaces and repeat for all your valves !!!!
Errr, I have a very nasty and quick way to lap 'em in. This is likely to result in the purists vomiting and spitting out their teeth but:
First, lube the shaft!!!!!!!!!
Wipe on some grinding paste onto the seat, insert the valve into the guide and grab the valve stem gently in a battery drill!!
Using your finger tip as a pressure guide on the head of the valve, spin up the valve and just keep lifting the valve off its seat every second or so.
Requires only slight pressure on the valve head and keep the bloody drill steady.
Very quick and as rough as guts but works surprisingly well if you are rather careful about it!!!
Sorry guys, I had to detail this one!!!! ready...set......PUKE!
L8tr
E
Im not a complete idiot, quite a few parts are missing....
tassupervee wrote:Errr, I have a very nasty and quick way to lap 'em in. This is likely to result in the purists vomiting and spitting out their teeth but:
First, lube the shaft!!!!!!!!!
Wipe on some grinding paste onto the seat, insert the valve into the guide and grab the valve stem gently in a battery drill!!
Using your finger tip as a pressure guide on the head of the valve, spin up the valve and just keep lifting the valve off its seat every second or so.
Requires only slight pressure on the valve head and keep the bloody drill steady.
Very quick and as rough as guts but works surprisingly well if you are rather careful about it!!!
Sorry guys, I had to detail this one!!!! ready...set......PUKE!
L8tr
E
HeHeHe.....was waiting for someone to post this "method"!!!!:thumb:P:P
yeah sorry dude, I could not resist it. I gotta say I have employed this method on many occasions with remarkable success.
It seem I am not the only one to employ it then eh???
Muwaaaaahahahahahahah
L8tr
E
Im not a complete idiot, quite a few parts are missing....
i too have used the drill method, back when i worked in a motorbike workshop. it's really handy for the tiny valves in some bikes which are impossible to get a suction cup onto....
you've just gotta make sure you don't put any sidways pressure on the drill, could end up with the valve seating kinda off centre, and i spose it probably wouldn't be too good for the valve guide either.....
Lol
the same thought crossed my mind while I was lapping them in after spending ages getting one valve to seat properly, the rest took a lot less work tho
thanks for all the info dudes 😀
I remember my dad doing the sidevalve Briggs & Stratton motors with the suction cup. When I would help him I would use the drill too. He didn't like it done that way as he was of the old school. I just wanted to go for a ride on my pushbike or for a swim, so I wanted to get it done as quick as possible. 🙂
I think the 'drill method' could be refined by inserting the shaft end of the valve into a short piece of tight fitting rubber tubing then putting the other end of the rubber tubing into the drill chuck. Inserting a bolt shank into the rubber tube at the drill end will stop the chuck from collapsing the tube.
This method will reduce the tendency for any bending loads inadvertantly applied to the shaft whilst rotating your valves.