I see no obvious reasons why not as long as the engine is fully supported. There will be no neutral light and that might trick the starter relay.

Before disassembling the clutch be sure and mark the three pieces for the exact same re-assembly. It's the perfect time to replace the main seals (engine and gearbox) and the oil pump o-ring.

Thanks Wobbly, and good info on the clutch assembly and seals. It brings up another conundrum I seem to have gotten myself into; after securing the armature bolt so it could not move forward, I marked the flywheel when at "OT", finagled the bolts off the flywheel and pulled it with a makeshift jig...but I managed to lose my mark on the flywheel in the process. I can't swear the flywheel wasn't moved during the "pulling" process. There is white paint on the in the recess in middle of rear main seal should this be aligned with flywheel's "OT" mark? Or is this a non-issue, and I should just turn the armature until I have full "up"stroke with compression and mount the flywheel at that time with "OT" in window?I've been away from working on the bike for some time, so all this info is really, really, helpful.Steve (aka Sebascodegan)

I have some issues with my gearbox (can't get it to shift - been setting in garage for years) and have taken it off the engine of my 1971 60/5 (75/5 jugs/carbs). While I'm getting the gearbox issue straightened out, I wondered about using the electric start to get the motor running so as to allow me to tweak the carbs and possibly timing.

Can that be done, or am I missing something obvious?

You can but I would not do it.

If you have the stock points the timing is set with a static light, engine not running. Do that any time.

If the tranny is out then the battery is too so you have to rig jumpers, the airbox is apart so tuning the carbs will have to be redone when that is back together, the drag of the transmission is missing so again the carbs will need retune, The neutral switch will need jumpered out----using the clutch switch will be weird seeing as how the tranny end of the cable is hanging in the breeze. Overall a whole lot more work to do than just doing a carb adjust when it is back together.

'meanwhile' kind of projects are the complete major service, replacing carb jet o-rings (leave the butterfly shaft + diaphragm + enricher alone), replace the fork internal rubber, likely dissolved if the oil wasn't changed once a year, service both perches, all greases, etc. If you have, and follow, the major maintenance schedule, you will be plenty busy.

Overall I personally do not subscribe to the while-I'm-in-there school of mechanicing. I fix things when they tell me they need fixed. This saves money (for gas) and time (for riding). Precious few things are worth doing just because you are doing something else. What you get out of being in there once is experience. If you have to go back in 2 years you will be a whole lot faster.

edit: I didn't see your second post when I made mine. Yeah, you got an oil leak needs fixing and you need a new oil pump cover. I would put the Left cylinder on OT and just eyeball the OT mark in the inspection window. You cannot be a tooth or so off and still get all the bolts in. You must keep the crank blocked at the front o do not remove the blocking to turn with the rotor bolt. just eyeball flywheel, but some bolts in finger tight to hold the crank from fore/aft movement, then turn the crank and check timing mark.

As my friend Arni has pointed out, there is nothing sacrosanct about the OT mark. You needn't face Mecca with your torque wrench, or any such.

"OT" simply means 'On Top' indicating that both pistons are at TDC. Stick a pencil down the spark plug hole and get it close. Then put the OT mark in the window. There are 5 bolt holes, so either you are smack dab on it or you are in front or behind by 72°. In other words way off, or right on the money. I think you can do this.

Without looking I suggested new seals and o-rings. This is not simply "while-I'm-in-there school of mechanicing". This sure knowledge that seals and o-rings have a maximum life of 40 years. Don't look now, but the photo says your time has expired. 😛

Again, to install the seal, get a product called "P80 Emulsion". It only takes 2-3cc's per seal. You can thank me later.

All the best.

"You needn't face Mecca with your torque wrench, or any such."

Thanks all. I think I'm gonna like this place.

I'm pretty much resolved to replace the seals. That, and what I thought was a stuck clutch were my original reasons for getting in there. I rebuilt the carbs and started the engine a few times before taking on the removal of gearbox, and clutch assembly.

As such, and given Arni's good reasons for holding off on carb tweaking, I think I'll just replace the seals/o-ring for now. Still plenty to do beyond that. P80 Emulsion, huh? I'll look into it.

I have another question, but I'll open another thread with appropriate subject line re a question I have on the gearbox.

gotsta replace the oil pump cover too with the new bolts. those bolts let you get a torque wrench on it and give better compression on the o-ring.

Thanks Arni. Duly noted and added to my needed parts order list. For the rear main seal, is there a workaround to the $50 seal press tool I've seen advertised?

a lot of those seal tools are just mandrels. a rim to catch the seal and a stub in the center to keep it centered up. Sometimes a surface to control seal setting depth. I'm a block o' wood and a hammer kinda guy but I can make blocks of wood any size I like.

where did you find a 50$ tool? Cycle works wants $45 for theirs. Looks like the BMW/cycleworks tool is a press type tool that uses the flywheel bolts. MArk where the flywheel is again.

did you check with your local airmarshal (wobbley??) for an ABC tool pool loaner?

Did you try heating the case and using that lube and your thumbs? I dunno, never done it. Being a special snowflake my rear main seals never leak.

observe old seal depth before removing. If the old seal has worn a groove the new seal can be set a bit deeper to run it on fresh metal. (well, it works on VWs anyway)

You'll get a lot more help if you'll simply put your general locale in your profile.