[Dr. Zo]

I'm putting my cases together and an having a bit of difficulty in remembering where the various studs go in each case before assembling. It may be I am missing a stud or something like that. This is a 1967 T120R. Is this the correct placement, 2 studs in the primary side case on the aft end, and two studs in the timing side case on the outside for the transmission case. I thought there might have been another stud somewhere and can't quite tell from the parts manual what goes where. Thanks for any help!

 

[Slippery Sam]

View attachment 802395
I'm putting my cases together and an having a bit of difficulty in remembering where the various studs go in each case before assembling. It may be I am missing a stud or something like that. This is a 1967 T120R. Is this the correct placement, 2 studs in the primary side case on the aft end, and two studs in the timing side case on the outside for the transmission case. I thought there might have been another stud somewhere and can't quite tell from the parts manual what goes where. Thanks for any help!

There is one stud (4) that goes in the top hole, the lower hole has a bolt (43). Gearbox studs are correct.

 

[Dr. Zo]

There is one stud (4) that goes in the top hole, the lower hole has a bolt (43). Gearbox studs are correct.

View attachment 802413

Thanks Sam. I believe the PO of this engine used a stud in place of the #43 bolt, which is what confused me. So when taking the engine apart I did not have the #43 bolt, but instead 2 of the #4 studs. Now I am wondering if I can go ahead and put it together with the two #4 studs, as it doesn't seem to have any clearance problems. Thanks for your comments!

 

[Dr. Zo]

Pressure relief valve - So I was cleaning some of the parts from this engine and took the pressure relief valve apart and found that it was missing the piston, everything else was there but no piston. So I am wondering if anyone knows what would be the consequence of running an engine with the pressure relief valve missing the piston? Thanks if you have an idea!

 

[GrandPaulZ]

Pressure relief valve - So I was cleaning some of the parts from this engine and took the pressure relief valve apart and found that it was missing the piston, everything else was there but no piston. So I am wondering if anyone knows what would be the consequence of running an engine with the pressure relief valve missing the piston? Thanks if you have an idea!

The result would be mostly bypass, and very little flow thru the crank which would inevitably sieze up the rod bearings.

 

[Dr. Zo]

The result would be mostly bypass, and very little flow thru the crank which would inevitably sieze up the rod bearings.

Thanks, glad I decided to take this apart.

 

[Dr. Zo]

Rickman gearing. So I am trying to figure out what size front and rear sprockets to use on my Rickman build. This is a standard Triumph T120 engine, rebuilt. What I've got for front sprockets are an 18 and a 19 tooth. For the rear I've got a 49 and 60 tooth. I'mm planning on using this mainly for trails and fire roads and a bit on the street. I'd appreciate any advice on how to set up this gearing. I'm ok with getting different sprockets - I just have these now. Thanks.

 

[steve welte]

those holes in the case some one drilled I like to tap and put in set screws to seal them with locktite. Install the seal on the crank. Use your regular breathing method and if you want more case venting use a rocker box vent hose. If you don't tap all the way though then the set screws cannot ever fall into the crankcase. doesn't hurt if there is some exposed end of the screw into the primary. I've nevr like sharing any primary with crankcase even though many engines did that. I prefer separate so I can use ATF in the primary. It gets rid of most chain stretch.

 

[GrandPaulZ]

... if you want more case venting use a rocker box vent hose.

That can starve the cams & followers of proper lubrication.

 

[Dr. Zo]

I decided to return the engine to the original venting, so had the holes welded shut and will vent the case as originally intended. This is how I have my first engine vented and have had no problem with it so far.

 

[StuartMac]

Hi,

Rickman gearing.
standard Triumph T120 engine
18 and a 19 tooth
49 and 60 tooth
rear
planning on using this mainly for trails and fire roads and a bit on the street.
what size front and rear sprockets to use

According to the '67 650 parts book, most variants were fitted with 19-tooth gearbox (except the TR6C (18) and T120TT (17)). However, all appear to have been fitted with 46-tooth rear; 49-tooth rear is three teeth more, about equal to one tooth less at the front (i.e. = TR6C) = I'd go for 19t front, 49t rear.

Hth.

Regards,

 

[Dr. Zo]

Hi,

According to the '67 650 parts book, most variants were fitted with 19-tooth gearbox (except the TR6C (18) and T120TT (17)). However, all appear to have been fitted with 46-tooth rear; 49-tooth rear is three teeth more, about equal to one tooth less at the front (i.e. = TR6C) = I'd go for 19t front, 49t rear.

Hth.

Regards,

Helps a lot - thanks!

 

[Dr. Zo]

I'm putting my Primary together now and I noticed on the cover plate (for the final drive) that on the inside of the plate is a tit. Anyone know what this is for and if it has to be oriented in a particular way?

Also, what do folks use to seal this cover plate, I've heard some folks use silicone versus something like yamabond?

Thanks.

 

[GrandPaulZ]

That cap has an excellent machined fit, no goop necessary.
To this day, I never worry about what that nub is for.

 

[Dr. Zo]

That cap has an excellent machined fit, no goop necessary.
To this day, I never worry about what that nub is for.

Good to know. I'd rather keep things as clean as possible. Thanks.

 

[Dr. Zo]

As I proceeded to put my primary together I noticed in the box of parts from the previous owner is an ELECTREX WORLD LTD, CDI IGNITION, STK-102D. So the PO was going to install this on the Rickman I believe. I am wondering who has any experience with these systems? The instructions say this can be run with or without a battery. It seems this unit does not need to have any part replaced in the timing/points cover, as the spark is generated from the rotor/stator, to the CDI, to the HT-2 coil to the plugs. I'd appreciate any comments on this type of system for my T120R, 1969, motor. Thanks.

 

[StuartMac]

Hi,

ELECTREX WORLD LTD, CDI IGNITION, STK-102D

The biggest disadvantage with them is, depending on the version, either they don't generate anything for lighting or only a maximum of 65W (i.e. about 5.5 Amps @ 12 Volts), maximum generating rpm unstated.

Plus, iirc, 1968 FMVSS says any bike made after 31st December 1967 and sold in the US, at least the rear lamp has to remain illuminated even if the engine stops. It was what finally drove the wooden stake through the heart of Lucas ET electrics.

Secondly, use the Forum Search in various old-Britbike forums, including BritBike itself to look for "electrex" then make a decision based on the results you find?

Hth.

Regards,

 

[Dr. Zo]

Hi,

The biggest disadvantage with them is, depending on the version, either they don't generate anything for lighting or only a maximum of 65W (i.e. about 5.5 Amps @ 12 Volts), maximum generating rpm unstated.

Plus, iirc, 1968 FMVSS says any bike made after 31st December 1967 and sold in the US, at least the rear lamp has to remain illuminated even if the engine stops. It was what finally drove the wooden stake through the heart of Lucas ET electrics.

Secondly, use the Forum Search in various old-Britbike forums, including BritBike itself to look for "electrex" then make a decision based on the results you find?

Hth.

Regards,

Thanks Stuart. I am going to give this system a try on this engine. Nice new parts and a new chance to see how it works.

 

[Dr. Zo]

Some progress on my Rickman build. So I've got the bottom end finished and installed the engine in the frame. Waiting to put on the top end just because it makes installing it a bit easier with having to move the engine a bit for alignment. It took a lot of adjusting and filing and some drilling to get the engine mounts, engine plates, etc. to align properly with the frame. Also needed to pay attention to the rear hub/wheel for alignment. I'm using a BSA quick detach hub for the rear and am having to alter the center boss of the brake plate to get clearance for chain alignment. I finally received the axle from Adrian Moss at Rickman. The Royal Mail was hacked a couple of months ago so it took 2 months for the delivery to happen. There is a lot more fitting on this build than I first thought!

 

[antoniogg]

Some progress on my Rickman build. So I've got the bottom end finished and installed the engine in the frame. Waiting to put on the top end just because it makes installing it a bit easier with having to move the engine a bit for alignment. It took a lot of adjusting and filing and some drilling to get the engine mounts, engine plates, etc. to align properly with the frame. Also needed to pay attention to the rear hub/wheel for alignment. I'm using a BSA quick detach hub for the rear and am having to alter the center boss of the brake plate to get clearance for chain alignment. I finally received the axle from Adrian Moss at Rickman. The Royal Mail was hacked a couple of months ago so it took 2 months for the delivery to happen. There is a lot more fitting on this build than I first thought!

View attachment 806574

Nice British racing green