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Shoots
08-07-2010, 5:52 PM
If my 67 t100c has bushing type bearings in the cases can they be upgraded to roller type bearings?

fozz
08-07-2010, 5:55 PM
If my 67 t100c has bushing type bearings in the cases can they be upgraded to roller type bearings?

Ya gotta change the crank , timeing side case an timeing gear cover, its well worth it
its easy to check just look at the case under the timeing case if its roller bearing it will have a lump protrudeing on the crankcase

Gepetto
08-08-2010, 12:45 AM
Why do you want to change from a bushing motor? If you need to rebuild it, have your crank checked out and mic'd out by a GOOD machine shop. Proper tolerence will provide a lifetime of use.

fozz
08-08-2010, 3:27 AM
Why do you want to change from a bushing motor? If you need to rebuild it, have your crank checked out and mic'd out by a GOOD machine shop. Proper tolerence will provide a lifetime of use.

Simple the timeing side bush was side feed relying on the journal in the crank for oil as bush wears bad oil feed , replace with roller bearing end feed to crank bearing wears no loss of oil feed , longer lasting engine stronger engine , ive don this a few times theres only benefits , now you explain the benefits of a bush timeing side bearing
pre units were a roller bearing all 650s roller bearing the bush was a weakness like in the
a10 bsa ,

Shoots
08-08-2010, 12:27 PM
I'm going to have it rebuilt anyway just because I don't know the history of it. What is a rough est of a bearing swap?

fozz
08-08-2010, 12:56 PM
you can pick up 2nd hand case crank , & cover not sure prices in your country but over here about
$ 260 for all 3 then bearing 50 or so. thats about $150 u s , it wont change engine nos as they are on the outher case, ,

whilst its down id also look at a big bore kit , if youve gotta bore it out pistons an rings fa that bit more id go big bore but thats me , the triumph 500 is a good motor. i think under rated m

good luck ride safe

Torch
08-08-2010, 1:00 PM
Simple the timeing side bush was side feed relying on the journal in the crank for oil as bush wears bad oil feed , replace with roller bearing end feed to crank bearing wears no loss of oil feed , longer lasting engine stronger engine , ive don this a few times theres only benefits , now you explain the benefits of a bush timeing side bearing
pre units were a roller bearing all 650s roller bearing the bush was a weakness like in the
a10 bsa ,

I agree with you about bushed motors like those early 500's, but the BSA had another problem with the bushing as it wore the crankshaft oil pump drive gear would seperate from the oil pump under hard power, right when you need the oil presure, at least the Triumph's still had a cam driven piston oil pump working harder with the RPM's

fozz
08-08-2010, 4:03 PM
exactly torch , with the B S A you had to do a devimead type conversion machineing the case welding an drilling the crank ect ,,.lucky triumph recognised the problem and changed the castings to accomodate bearing so you just gotta get a 2 nd hand replacement , makes the job easy