decomp spring is soft

anyone else find this?

the decomp is really slow to flop back home and sometimes needs to be prompted almost?

i have fitted a few now and one is truly spring loaded and the next is like half stuck and needs prompting!

regards

Taffy

so (to a thicky) what are you saying about standard set up?

regards

Taffy

the thing is...the new decomp spring essentially has it's tail go across the middle of the end of the coils. you would expect to put the lobe into the 'C' part but you can put it outside this. i've seen this trouble before but i can't recall how i cured it.

regards

Taffy

i've sorted this today. if anyone will host the photo please PM me your email address.

i have taken the long arm of the spring as it straightens to move away from the coils and i've bent it back to bring the point striaght down onto the flat of the cam. this has the effect of twisting the spring a further 60-90 degrees.

the decomp works a treat now.

regards

Taffy

i haven't been able to upload photos for two years! no idea why.

anyway PM me an email address as i don't think i have either of yours.

cheers lads!

taffy

cheers eric

by the way the ladder IS for sale. you're all wilcome to bid me! LOL!!!!

anyway, can't recall right now but the spring is only coiled up about 3/4-of-a-turn and as you can see - i've added another 33%

regards

Taffy

yet again i've had trouble, even with the above hook. there is considerable friction between the bobweight and the hardened shoulder of the cam.

hopefully, below, eric will plonk a couple more photos to demonstrate this.

when the cam is the wrong way up, the decomp bob hangs below the cam and can't get back to the inside shoulder. so we have no decomp. this means kicking full compression!

on assesment it becomes clear why!

the decomp spring has far too many turns to it. the grooved shoulder for the location of the spring needs to be nearer the exhaust lobe to allow the spring to become free'd up. IT'S COIL BOUND! it's not only coil bound but means that the decomp lobe is forced hard against the shoulder of the cam. because both surfaces are flat but unpolished there is a lot of friction.

my latest answer has been to bend even more spring but this time let it run around the body of the cam.

you'll have difficulty spotting it in the photos but like for a shiny wire!

this gives me more tension but slightly less wire. all i could do on this occasion was to grind the shoulder of the cam slightly so the bobweight has no friction.

in the future i would like the thinnest shim of say .005" (0.1mm) on the base of the decomp shaft to seperate the cam from the weight.

regards

Taffy

thanks eric and adding to what i said previously: you know those african tribeswomen? they have extra long necks and rings round them - well now you know how the decomp feels!!!!

oh and seconds later i spotted the washer on the bench for that far bolt so don't have a go at me.

regards

Taffy

whato mate!

yes you can recoil the whole thing up and get it working again. just make sure that it's tight on the 'D' section.

my spring has 16 coils at the back and 14 at the front.

you'll know to look at the tip[ of the lobe and its condition?

nothing else to say really - thats about it.

regards

Taffy

my latest way of fitting the spring is to unroll it a full turn and a bit until the wire points in the same direction as the other end that bisects across the middle. i then snip 30mm off and fit. by the time i've wound it up now it's just about spot on. and i can always make the inverted 'V' with the tail to make it even stronger if i need too.

regards

Taffy