Pre units are a pain in design. The primary chain is adj by moving the transmission to & fro and then that throws the rear drive chain out of adj. Also the primary chain is just one row chain that is not as big as the drive chain. Also the preunits have a 8bolt head and evey one has cracked, but they run with that crack from the valve seats to head bolt and does not loose compression. Mine is like that and can not notice it, but a swap to a later cylinder and head would be an easy remedy.
getting the torsion bars replaced with a "spring valve" setup. Ported,5mm valves, epoxy coating in the camshaft area for faster oil returned, new valve guides. Terry Naughtin of Team Hansen Racing is doing it up in Illinois near Chi-town. Very experienced individual with the Honda twins.
What work is being done on the head? Where did you have the work done? Mine has a cracked head, but the crack goes into a big bolt hole so nothings lost. Typical of the pre unit 8 bolt heads. I'd like to get a nine bolt head,64-70; they don't crack! Sometimes it's scary riding an old bike, you never know what might go south. I blew up a 67 once, the wrist pin froze in the bushing and wallowed out the con rod, then it broke the conrod and piston into pieces.
No snow in Dayton Ohio yet. Just freezing temperatures and icey roads. Sucks. In the Spring through Fall, I try to get the 59 out every day, even if it's just to go to a fast food store, or any excuse I can use. My wife said she'd bury it with me or use it as a headstone!
The Engine looks similar to Royal Enfield.
Is it a twin cylinder?
I love to own it.
Thanks for posting...
vaazstorm 1 year ago
yes i want a pre unit! restoring a 66 bonnie frame up , split cases etc and ride a 70 tr6
cavemandan 3 years ago
Pre units are a pain in design. The primary chain is adj by moving the transmission to & fro and then that throws the rear drive chain out of adj. Also the primary chain is just one row chain that is not as big as the drive chain. Also the preunits have a 8bolt head and evey one has cracked, but they run with that crack from the valve seats to head bolt and does not loose compression. Mine is like that and can not notice it, but a swap to a later cylinder and head would be an easy remedy.
trimphbsa 3 years ago
Get a real bike. Faggot.
pazleen 3 years ago
@pazleen he has a Harley they are so fag
terryjohn 1 year ago
getting the torsion bars replaced with a "spring valve" setup. Ported,5mm valves, epoxy coating in the camshaft area for faster oil returned, new valve guides. Terry Naughtin of Team Hansen Racing is doing it up in Illinois near Chi-town. Very experienced individual with the Honda twins.
zx12ryder 3 years ago
just waiting for my head to come back that i sent out. cant wait to get it on the bike.
zx12ryder 3 years ago
What work is being done on the head? Where did you have the work done? Mine has a cracked head, but the crack goes into a big bolt hole so nothings lost. Typical of the pre unit 8 bolt heads. I'd like to get a nine bolt head,64-70; they don't crack! Sometimes it's scary riding an old bike, you never know what might go south. I blew up a 67 once, the wrist pin froze in the bushing and wallowed out the con rod, then it broke the conrod and piston into pieces.
trimphbsa 3 years ago
very cool, wish I could be riding,foot of snow out.all I can do now is go out in garage and keep my bikes company
poisonsunshine 3 years ago
No snow in Dayton Ohio yet. Just freezing temperatures and icey roads. Sucks. In the Spring through Fall, I try to get the 59 out every day, even if it's just to go to a fast food store, or any excuse I can use. My wife said she'd bury it with me or use it as a headstone!
trimphbsa 3 years ago
nice bike...very clean.
zx12ryder 3 years ago
Thanks, it looks better on video than in person, but it still grabs attention at every gas stop. Hows your 450 comming along?
trimphbsa 3 years ago