LCGB Forums

Hi folks,

I'm looking to upgrade my barrell and piston on my Series 1 Framebreather however I have the original short barrell / piston set up / crank. Would I just be able to "plug and play" a cylinder kit (looking at the Gori Replica kit) or would I need a new crank too. I'm trying to keep it as standard as possible but it's time to bite the bullet and get some extra performance.

Cheers all

Wayne

The crank if original will have a small end bush rather than a roller bearing. These can be replaced if you have a reamer tool.
The crank flywheel side bearing is lubricated by the petrol/oil mix.
These two items were changed on later Li's due to wear problems on the more powerful engine. For that reason it would be a good idea to change your 55 year old crank and flywheel housing now, rather waiting for problems later.

Pete

Yeah I went thru the same as you- needed to improve the performance of my framebreather but really wanted to keep it as original as poss keeping as much of the engine as it should be
viewtopic.php?f=19&t=664
(White/blue breather)


But!..... For reliability You really do have to change the crank- it's brass little end and poor bigend quality really wouldn't last very long at kind of revs and modern kit does... I also found no one does a oil/petrol fed bearing crank upgrade so not only did I have to upgrade the crank (I went for an Italian MEC) but also had to fit a new maghousing!... And obviously new gp main bearings and really because of the unreliable s1/2 four pole stata ( the coils come loose and jam the flywheel) I also upgraded to a gp stata/ flywheel to.
So in the end it was new topend, crank, maghousing, bearings, stata, flywheel, carb, exhaust!... And also different sprockets ( and chain) of course and upgraded clutch (5 plate) and springs !,
However the gearbox, clutch spider, layshaft etc I kept!
You may want to change the chaincase to... Which are weak around the kickstart shaft when you have have more compression!, I fitted a spanish s2 one

Cheers Pete & Nobby for your replies, Food for thought!!