Rocker geometry set up, valve spring binding!!!

[Mike Cott]

I’m in the process of setting up my 1.4 rockers but when I turn it over by hand the valve spring bind stopping the rotation.

If there is a decent web page for setting the rockers up please post up here, better still a YouTube video would be brill.

Tia
Mike


Sent from my iPhone using Tapatalk

[baz]

Use a light spring for set up. Adjustable pushrod spring fits well.

[Mike Cott]

Just read that Baz, I’ll swop out the dual HD’s for a stock single I reckon. Although I think I’ve sussed it, piston had a mark on it when I stripped the head off, reckon the piston and valve are hitting each other.

FK8 cam and 1.4 rockers so a lot of lift

Any ideas other than pocketing the piston tops?

Thanks Baz


Sent from my iPhone using Tapatalk

[baz]

Just read that Baz, I’ll swop out the dual HD’s for a stock single I reckon. Although I think I’ve sussed it, piston had a mark on it when I stripped the head off, reckon the piston and valve are hitting each other.

FK8 cam and 1.4 rockers so a lot of lift

Any ideas other than pocketing the piston tops?

Thanks Baz


Sent from my iPhone using Tapatalk

I've similar lift and 1.4s and 0.4 deck, shouldn't hit unless your cam is indexed wrong. That's something I've done in the past 

[Mike Cott]

Just read that Baz, I’ll swop out the dual HD’s for a stock single I reckon. Although I think I’ve sussed it, piston had a mark on it when I stripped the head off, reckon the piston and valve are hitting each other.

FK8 cam and 1.4 rockers so a lot of lift

Any ideas other than pocketing the piston tops?

Thanks Baz


Sent from my iPhone using Tapatalk

I've similar lift and 1.4s and 0.4 deck, shouldn't hit unless your cam is indexed wrong. That's something I've done in the past 

The deck height I have .403mm, is your measurement in mm’s I predict your in inch’s


Sent from my iPhone using Tapatalk

[baz]

A zero missing in mine, should have said 0.040 inch or 1mm.

Your deck is 0.4mm? That seems too tight as 1mm generally recommended as minimum.

Still shouldn't cause valves to hit though

[Mike Cott]

A zero missing in mine, should have said 0.040 inch or 1mm.

Your deck is 0.4mm? That seems too tight as 1mm generally recommended as minimum.

Still shouldn't cause valves to hit though

I’ve got a 1mm cylinder shim so think I’ll try that tonight to bring the deck up to 1.4mm deck and report back. I wanted to keep my CR up this shouldn’t affect it to much


Sent from my iPhone using Tapatalk

[richie]

Mike

Baz is correct 0.4mm is to tight, but if it hits now even at 1.4mm it will be to close for valve to piston clearance, what heads are they and are they machined for compression? what cc in chamber?

I have built quite a few engines with fk8 and 1.4 rockers and never had to notch pistons yet s makes me think something else is not quite right

cheers Richie

[Mike Cott]

Mike

Baz is correct 0.4mm is to tight, but if it hits now even at 1.4mm it will be to close for valve to piston clearance, what heads are they and are they machined for compression? what cc in chamber?

I have built quite a few engines with fk8 and 1.4 rockers and never had to notch pistons yet s makes me think something else is not quite right

cheers Richie

They’re CB Ultra mags I’ve bought used so don’t really know if they had work done, they’re 57cc as Ive measured.


Sent from my iPhone using Tapatalk

[baz]

You certain cam is aligned correctly with cam gear? Dot to slot? And cam gear correctly aligned with crank?

[Mike Cott]

You certain cam is aligned correctly with cam gear? Dot to slot? And cam gear correctly aligned with crank?

Lots to double check this week I reckon


Sent from my iPhone using Tapatalk

[Mike Cott]

Stripped it down here is how it’s set up, feel like there’s something blindingly obvious just not jumping out at me





Sent from my iPhone using Tapatalk

[Mike Cott]

The crank gear only has that small mark but at 180 opposite sides of the gear if that’s relevant


Sent from my iPhone using Tapatalk

[Garrick Clark]

Looks wrong. That crank cog mark isn't the 2 dots. There further round the cog and can be almost invisible

[Garrick Clark]

In fact. It's definitely wrong

[Fastbrit]

Note the single dot on the cam gear is in line with the slot in the end of the camshaft. Then note the two timing marks on the crank gear are directly opposite the slot for the Woodruff key.

Also, you 'may' have installed the crank gear back to front, meaning the two dots are on the back and out of sight. In which case, you'll need to pull it off and turn it round...

[Mike Cott]

I’ll see if I can get a view for the dots on the crank gear from the rear, hope so it was a pig to get on. Crank had to go in the fridge for an hour to get it on, wife loved it 🤷🏼‍♂️


Sent from my iPhone using Tapatalk

[Garrick Clark]

You won't have to take that cog off. That dot in the above pic is on the same side as the 2 correct dots. I had to use an eye glass to see them as they are so poorly etched onto the cog

[baz]

I’ll see if I can get a view for the dots on the crank gear from the rear, hope so it was a pig to get on. Crank had to go in the fridge for an hour to get it on, wife loved it 🤷🏼‍♂️


Sent from my iPhone using Tapatalk

Did you heat the gear or just freeze the crank? Heating the gear is easier.

[baz]

I’ll see if I can get a view for the dots on the crank gear from the rear, hope so it was a pig to get on. Crank had to go in the fridge for an hour to get it on, wife loved it 🤷🏼‍♂️


Sent from my iPhone using Tapatalk

Did you heat the gear or just freeze the crank? Heating the gear is easier. Finding the dots should be easy if you follow Keith's picture above.

[Mike Cott]

I’ll see if I can get a view for the dots on the crank gear from the rear, hope so it was a pig to get on. Crank had to go in the fridge for an hour to get it on, wife loved it 🤷🏼‍♂️


Sent from my iPhone using Tapatalk

Did you heat the gear or just freeze the crank? Heating the gear is easier.

Had to do both Baz


Sent from my iPhone using Tapatalk

[Mike Cott]

You won't have to take that cog off. That dot in the above pic is on the same side as the 2 correct dots. I had to use an eye glass to see them as they are so poorly etched onto the cog

Found them, as you said they where so difficult to see


Sent from my iPhone using Tapatalk

[Mike Cott]

Put back together in the correct order and hey presto!!!  All good 🎉🎉
Thanks for the help guys


Sent from my iPhone using Tapatalk

[richie]

Put back together in the correct order and hey presto!!!  All good 🎉🎉
Thanks for the help guys


Sent from my iPhone using Tapatalk

 

[Mike Cott]

Put back together in the correct order and hey presto!!!  All good 🎉🎉
Thanks for the help guys


Sent from my iPhone using Tapatalk

 

Good advice is indeed priceless Richie 😎


Sent from my iPhone using Tapatalk