Suzuki GS550E — Quarter Turn Throttle Conversion.

 Converting your throttle tube to a 1/4 turn.

I'm pleased to say the GS550/673 is going really well — the engine has been faultless so far. One thing that is annoying me though is how bumpy the front end is, and it's really obvious since sorting the Bandit. The 1200 front end is now feeling incredibly refined and plush after a fork oil change, so I wanted to change the springs in the front of the GS to try and help her out.

As luck would have it, a pair of new Progressive springs came up on eBay for $110 delivered. Result! Although the general consensus now is to fit straight-rate (linear) springs, this was a bit of a bargain. However, they got stolen on the day they were delivered by some scrote who told the postie that they lived at my house. And that was the smaller of three parcels! Luckily I got my money back via Paypal, but that's besides the point. I was not impressed.

Suzuki GS Engines — Checking Valve Clearances.

Basics — why do we need clearance?
In an ideal world, the combustion chamber in an engine would be completely airtight during the compression stroke. However, due to basic mechanical inefficiencies, there will always be blow-by somewhere. But by keeping this to a minimum, your engine is able to produce good power. 
Possible ways for the air/fuel mix to escape could be via the piston and rings, through a failed head gasket or the valves in the cylinder head. Because we're dealing with valve clearances today, we'll stick with those. 
In modern engines, the poppet valves in a four-stroke engine are either machined perfectly to form a seal against the 'seats' in the head, or lapped in with grinding paste to match them together (older engines). Springs then hold them tight against the seat and, voila, no air leaks. 

Suzuki GS550E. In this pic you can see the two camshaft lobes above their respective bucket and shim. The cam cap is removed because some clown (previous owner) stripped a thread — in fact they mullered a few of them and decided to replace them with some coarse-threaded bolts! Marvellous.