Valve spring compressors?

[northwind]

When i finally pop the heads off and fit the busa pistons and bump teh compression, I'm going to do a rough cleanup of the ports and check the valve seals etc... Which needs the valves out. DO I actually need a spring compressor tool, or is there any way to bodge this? If I do need one, anyone recommend a suitable one? I'll probably only use it once on the SV so, cheap is good :D

[jambo]

Machine mart do a couple none of them are expensive, picked one up for Rictus a while back when the trusty scoot bent a valve...

http://www.machinemart.co.uk/shop/product/details/cht461-ohc-valve-spring-compressor

Edit: You'd need to chat to Rictus about whether the thing was actually any good, mind....

[carsounds_dan]

i got one when i did the valves on my zxr but i'll be ****ed if i can remember where i got it from.. i'll have a look

[squirrel_hunter]

When i finally pop the heads off and fit the busa pistons and bump teh compression

At risk of a derail...

Can we expect a detailed description of whats doing?

[Jase22]

Another vote for Machine Mart. I have this one, all you'd ever need to do bike or car.

http://www.machinemart.co.uk/shop/product/details/cht434-multi-valve-spring-compressor

[northwind]

At risk of a derail...

Can we expect a detailed description of whats doing?

Well, depends. If it works brilliantly, then yes. if it fails epically, I shall destroy all the evidence and claim I changed my mind. My honest opinion? It's not actually worth doing. But it's interesting to do, and good for SV comparing contests ;) The gist of it is- take heads and barrels off, get barrels honed out very slightly (the bores are the same, officially, but in reality ever so slightly bigger) then reassemble with a thinner head gasket. Slightly lighter pistons + more compression.

I'll pay a visit to my local machine mart then- thanks chaps!

[yorkie_chris]

Are you going to be using new rings or what? Surely secondhand ones will be run-in for whatever it was in previously.

Also how much needs to be taken out of the bore?

Where do you get the thinner gaskets?

Has anyone got some info on what areas of the head need to be shaped for good flow? Was thinking of making a flowbench as I've got a couple of spare heads... but big cfm doesn't mean good useable power....

P.s if you can find a set of 4 pistons then I wouldn't mind splitting the price...

[northwind]

The amount of the hone's very small, it's either the world's biggest hone or the world's smallest big bore. Don't have the exact size, I'm leaving that to YPE who'll be doing the bore for me. And I should use new rings, but these are barely used, so they reckon they'll be fine. Not a decision I could call myself but they know what they're doing I reckon.

You get thinner gaskets by splitting the standard ones, they're layered steel- so remove a layer, or two. I could get them to machine the heads down slightly instead but the split gasket approach's well tested. And after all, I'm not aiming for max compression, just a modest hike.

I'm not going to do significant reshaping of the heads, just clean-up and polishing/texturing. The exhaust valves look to be pretty shrouded to me but I'm not sure if I want to screw with that too much.

Like I say, this is more or less a "something to do on a wet saturday" rather than a proper tuning project ;) It'll give some benefits but I don't plan to go for best results, just reasonable ones. Bike's done 40000 miles so it gives me a chance to give the heads a proper health check too.

[instigator]

Buy them from Halfords, use them carefully, take them back saying they were the wrong size and hey presto, refund. ;)