im just doin them now on a engine im building.... ive got the valve shim calculater up on screen... but dont really need it as ive got loads of shims so dont have to be precise of what goes where,,, just measure whats in,,, and change it for a smaller one accordingly.. simply... but isnt it soooooo effing boring..
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Why have hydraulic tappets never caught on with bikes? OK I understand not using them in full on sports bikes but I'm only aware of Honda 750s and a few HDs using them.
Ian Newham: Why have hydraulic tappets never caught on with bikes? OK I understand not using them in full on sports bikes but I'm only aware of Honda 750s and a few HDs using them.
HD, save for the V-Rod, all have hydraulic lifters. I've replaced one noisy one (easy job if you have collapsible push rods) and defo think they make sense.
problem with shims is keep replacing all the bigger ones with small ones.... so just ending up with loads of big shims...
i tried to grind one down once... superglued it to my finger to hold it flat on the side of the grinding wheel.. held it on there till it burnt my finger,, several times.... then flattened it for a while with a good fine file,, then rubbed on emery paper for ages... i managed to take it down about 0.02..
lord stuart: problem with shims is keep replacing all the bigger ones with small ones.... so just ending up with loads of big shims...
i tried to grind one down once... superglued it to my finger to hold it flat on the side of the grinding wheel.. held it on there till it burnt my finger,, several times.... then flattened it for a while with a good fine file,, then rubbed on emery paper for ages... i managed to take it down about 0.02..
It's cheaper to grind down a few 10 pence pieces as they are about the same diameter as a shim .....now that's Yorkshire ingenuity
I found the job a piece of pi** on my 595, but they're due to be checked on my GSXR soon so i might leave that to the experts......i've heard it's quite tricky on them
Goodygixxer: I found the job a piece of pi** on my 595, but they're due to be checked on my GSXR soon so i might leave that to the experts......i've heard it's quite tricky on them
Like everything else, it's easy if you have the ability. The risk element arises from getting it (very expensively) wrong!
Ian Newham: Why have hydraulic tappets never caught on with bikes? OK I understand not using them in full on sports bikes but I'm only aware of Honda 750s and a few HDs using them.
I think hydraulic lifters pump up at high revs, don't they...? I know with a Rover V8 if you wanted to increase the rev range you had to replace the hydraulic lifters with solid ones...
The new Fiat 500 and Alfa Guiletta new Multiair engine uses hydraulic valves in the cylinder head developed in conjunction with Yamaha - which possible explains why the Yamaha M1 was sponsored by Fiat as all of the MotoGP bikes changed to hydraulic valves in the last few years to get at the higher rev range available and thus more hp. Conventially sprung valves were prone to 'bounce' at certain harmonics at higher revs.
The Fiat 500 TwinAir 875cc engine was voted Engine of the Year in 2011.
According to Wikipedia, its an electro-hydraulic variable valve actuation technology controlling air intake without a throttle valve in petrol and diesel engines.
So my guess is, sportsbikes will chase higher and higher rev ranges and hydraulic valves will enter into the production market and maybe we could get our hands on mechanically simpler engines? irony.
i tried to grind one down once... superglued it to my finger to hold it flat on the side of the grinding wheel.. held it on there till it burnt my finger,, several times.... then flattened it for a while with a good fine file,, then rubbed on emery paper for ages...
lord stuart: problem with shims is keep replacing all the bigger ones with small ones.... so just ending up with loads of big shims...
i tried to grind one down once... superglued it to my finger to hold it flat on the side of the grinding wheel.. held it on there till it burnt my finger,, several times.... then flattened it for a while with a good fine file,, then rubbed on emery paper for ages... i managed to take it down about 0.02..
i tried to grind one down once... superglued it to my finger to hold it flat on the side of the grinding wheel.. held it on there till it burnt my finger,, several times.... then flattened it for a while with a good fine file,, then rubbed on emery paper for ages...
i had done my shims perfect on my bike,,, just one valve was about 0.02 tight,, so thought hmmm ill bet i can grind it down that much to make a full set of perfectly set shims.. i just about managed 0.01 i think,, then thought,, feckit that will do..
i tried to grind one down once... superglued it to my finger to hold it flat on the side of the grinding wheel.. held it on there till it burnt my finger,, several times.... then flattened it for a while with a good fine file,, then rubbed on emery paper for ages...
i had done my shims perfect on my bike,,, just one valve was about 0.02 tight,, so thought hmmm ill bet i can grind it down that much to make a full set of perfectly set shims.. i just about managed 0.01 i think,, then thought,, feckit that will do..
ianleeds: More cylinders, and more vales, the worse it gets. Can you imagine what it was like reshimming a Z1300 ?
Did my Z1300 shims last year, it's actually not bad, having only 2 valves per cylinder (12 valves, comparable with a Hinckley triple then), also the shims are on top of the buckets, so they're done with the cams in situ But how about a CBX, with 24 valves to shim?
Just done the shims on my SV1000, only 8 to check, trouble is i needed to change an inlet on each cylinder, being a v twin means checking one fitted size then putting it back together to check the shim on the other cylinder, still a piece of piss cos it has gear driven cams and dont have to muck about with the cam chain
Beemster: What was wrong with the old locknut and adjuster? It were good enough for me dad I tell thee...
Probably all down to reducing mass in the valvetrain to avoid valve float but there are always examples contrary to accepted wisdom e.g. GPz500s have a 14K redline yet still have screw and locknut adjusters.
ZXR750s and ZX9R Bs had rocker arms between the cam and valve that you could slide to one side to change the shims without removing the cams.
We seem to have given up on a few things that make maintenance much easier just to boost a bikes redline. Its going to be a PITA having to remove the cams to do the clearances on my 7R bucket over shim was a doddle on the RS.
irony.
