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Discussion Starter · #1 ·
bought a pre 69 t120 650cc it has a broken conecting rod and aswell as the cylender is needing a new sleeve or new cylender all together

i bought the haynes manual, i need to get the rebuild dvd, i also bought a new cylender that is .30 over with pistons, but the head has a diffent bolt pattern aswell as one of the pistons is missing the rings, and have found out that i cannot get .30 rings, so i am stuck on what to do

A get a new matching head and get some .40 rings machined
B get a new head bore it out to .40 get new pistons
C send the original cylender out to get resleeved and get stock pistons

I am leaning towards C any idea on pricing? also i am going to order the clutch extractor tool any other tools i should invest in, aswell is there only one dvd and if there is more then one can anyone recomend the better one?

right now i am working on body work and getting the rolling chassis
 

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The oversize pistons and rings appear to be +0,020", +0.040" and +0.060" for pre-unit 650`s.
Also the head can be 8 or nine stud.
Dont know a lot about pre-units.
Broken con-rod?...these are usually sold in pairs and are expensive.
I recently bought new standard barrels and Hepolite piston assembly`s which cost £250.
($367)? for my unit Bonnie.
 

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l think you'll find '69,s are unit. So the second hand barrels must be preunit 8 studs. l would sell the barrels and go with Morgos, ect unless you are financially challenged. As this is a total strip down its, in for a penny, in for a pound. ( another Brit saying, cent for penny and dollar for pound!).That way you know what you're getting.
 

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*******:

You need to split the cases no matter what, so it's a TOTAL OVERHAUL for you.

Buy a new or good rebuildable set of cylinders (std, .020, .040, .060 & .080 are available) and NEW PISTONS & RINGS.

DO NOT do the final finish honing on the cylinders 'till you have your new pistons IN HAND. You need .0045 clearance on the bores AS MEASURED AGAINST THE NEW PISTONS. You also want .010 ring end gap when you place them one at a time in the freshly finished honed cylinders.
 
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