73 into 76

[Andy]

Hey,
Had time to get over the loss of the bike now(yeah right!) and decided to do an inventory of all the stuff i have in my workshop/sheds. I reckon i have enough to build the best part of two bikes so i`ll try again and sell the excess.
My question; Will the 73 motor go into a 76a frame without any headaches? The reason i`m asking is because i have at least one servicable motor and a ton of other parts(and 76a frame) and it seems stupid to not to use what i`ve got before i go collecting more.....
Cheer`s Fella`s
Andy

[stripes1976]

unfortunately not mate the engine mounts are no where near

[Andy]

Bummer,got a good 76 motor kicking about then?
Andy

[stripes1976]

i haven't at the minute but theycome my way quite a bit

[Andy]

Let me know if anything comes your way buddy,look`s like i need one....
Cheer`s
Andy

[Andy]

Out of interest i went into my workshop to trial fit a scrap 73 motor into my 76 frame and as far as i can see ALL the mounts line up,2x rear and lower mounts as well. It leaves the top mounts redundant but this leads me to my next question; Will the 76 head fit the 73 bottom end and work? This is purely to lose the top mounts and i`ve every intention of refreshing the head on my 73 lump anyway so i may as well use a 76 if it will work....
Andy

[Variablevalves suck]

Hi Andy,
Sure its a no. they share the same gaskets so everything will line up but if i remember the last time i looked in a 76a (while ago) they run a twin duplex type cam chain and the 73a has a single type, i may be wrong but you can easy take a look plus they maybe diferent lenghts i dont know.

[Andy]

Hi Andy,
Sure its a no. they share the same gaskets so everything will line up but if i remember the last time i looked in a 76a (while ago) they run a twin duplex type cam chain and the 73a has a single type, i may be wrong but you can easy take a look plus they maybe diferent lenghts i dont know.

Like i said it was just to get rid of the mounts really but i`m sure i read on `gsxr400.com` that a 73 head will fit the 76 so would probably work the other way round, but i could be wrong. I`ll stick with the 73 complete motor then and go from there...
How is your sp coming along Chris?

Andy

[templin]

yo dude look up my posts ive answered these questions if you cant get K708/712 castings (GK76 and Rf400) then you can mod the K706/707 castings firstly strip off the lower casting then the end rear bolt shoulder get machined 5-6mm shorter use shorter or mod the bolt and close the sub the motor will then fit in the 76 frame you will find that the spacing of the mount near those bolts are out mod as needed then that`s the sub in as for head yes it will fit use with barrel as gasket face on some 76 heads are a lil different and lastly again depend which head you might need a stud change and then its on all sorted if this is to much to attack you can fit all the 73 internals into the 76 castings remembering that the crank, clutch hub AND oil pump gear needs to move as a set match rest of parts as you feel fit the rods n pistons are the same cylinder head valves are different (hence different head among other changes) gearbox ratio on later 76 is different but gearbox's will fit across casting and so do selector forks oh there are different selector forks that the factory did change over the years no train smash just pay attention when assembling the selector bitz if the groove is wide it uses a "bearing" (all it is ,is a collar) if narrow no "bearing" if you using a bearing type selector fork on a drum that dont uses one omit the "bearing" and shorten the pin 2mm any other questions ?