dumb cam ques

[Anonymous]

first off i have a 82 gs1100g and it just will NOT start

has never started with the starter since i owned it it has for lack of a better term a "tight spot" in the engine

if u turn the engine with a wrench when the lobes on the intake cam start pushing the valves down on the middle cyls it gets REAL tight but once the go "over the top" the engine almost wants to spin itself

heres what we tried so far

crank has been sent to falicon straightened and a new end welded onn it

every valve has been out of the head checking for a valve binding on the guide

new timing chain whole engine has been apart 4 times since sept when i bought it trying to see whats binding up and everything LOOKS ok but when u put it back together it does THE SAME EXACT THING!

so anyways im kinda thinking i might have a bent cam (this is for sheer lack of anything better to try)(if u have a better idea by all means speak up)
what i was wondering is this
are ALL 2 valve cams the same? i realize duration and lift will probably be different but as far as lobe spacing etc are they alike?

in other words if i grab cams out of any 2valve will they work in my bike?

if so is there any in particular that are a good choice? a little "hotter" than what i have maybe?

the bike is REALLY clean and id hate to have to part it just cause i cant get cams for it or figure out what it needs

im to the point where id buy another engine and swap the whole thing if i could find one

the tight spot really has me up against a wall(beating my head on it)

thanx in advance
scott

[Motorcyclemodeller]

Sounds like cam warpage or possible severe head warpage...........or maybe the cam caps themselves are mucked up.

I would try a new set of cams, any GS 2 valve cams should work. I think 1979 750 cams are the hottest factory grinds for the 2 valve motors. (read that here on a thread recently).

Dr. Dre

[Anonymous]

EXCELLENT DRE!

thank you
ive ruled out head warpage due to the fack that i have even compression numbers (approx 130 psi) across the board

like i said we were kinda thinking cam warpage/bend

you could see that the engine had spit a shim out at one piont in its life and i kinda think the motor locked up then and bent the crank and possibly the cam

like i said the bike is REALLY clean low mileage original paint etc etc

i bought it off of some kid for 2bills thinking it would be an easy fix but i still only have 500 in it now
it will make a GREAT ride once i get her going

ill have to start hunting cams now i guess
thanx again scott

[skip]

with the plugs out is the tight spot still there? does it get better? I am using cam motion g-4 cams and i like them, they are very streetable but really give your upper rpm range some extra zip. I believe they make them for a two valve motor also. Befor i spent money on new ones I would go to a bone yard and see if you can swap in another stock pair to see if thats the problem. You can also pull the cams set up an dial indicater and check for runnout and warpage before you do any thing else

[Anonymous]

skip

the tight spot get somewhat better with no plugs but its still there
Y? is there something in particular that i should be looking for there?

im not planning on going with an aftermarket set of cams i was only wondering what all cams fit so i knew whether or not i HAD to find a GS1100 set

that might have been difficult at best lol

now that i know they ALL fit it broadens my search options somewhat

scott

[Jethro]

I had a damaged cam at the cam seat last year and bought replacement cams. I recommend you buy a complete used head. Might cost you a tiny bit more (might not) and it is worth it. I have been told from many reputable engine gurus that cams and head seats wear at the same rate, therefore putting a new cam in an old head is a bad idea as is old cams in an older or newer head. Anyone else have some input on this? I am curious if I got good information or not.

[Anonymous]

i wouldnt be adverse to buying a complete head or hell even an engine

provided i can find one and it isnt so far away so as to make shipping astronomical

i hear what ur saying about the head tho

id almost rather find a complete head so i can swap the whole thing out and almost definatly cure my woes

scott