RRussellTx - 1974 Commando 850 Project

htown16 said:

Are you rotating the sprocket while attempting to shift the gearbox?

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Yep, that helps a bunch but it still seems like it should be easier to hit the gears.
I'm going forward with the assumption that it's normal, but I tend to worry about everything...

I've always found dry shifting more crunchy than when riding. As long as you can get all four gears I wouldn't worry about it at this point. If you are still having problems when riding it is likely the hair pin needs a slight adjustment. Easy to do with bike assembled just pull the outer gearbox cover. One reason to never use gasket sealer on both sides of that gasket.

Another overdue update:

Finally got the Engine back from Big D Cycles last week and got it installed yesterday.
I also got the front wheel and tire ready.

Working on the rear wheel and installing the Primary side next.

After that, I'm looking for an order of assembly for all the smaller bits,

Battery Box, Ham can Air Filter, Carbs, Oil Tank, Electrical etc...
If anyone has a favorite list then I would appreciate you sharing it!

Install the battery tray and the horn before you go much further. It's impossible to access once you get the wheel and fender fitted. Test it first. Fit the small sub harness at the same time.

maybe its just me, but looking at that table . . . with no straps on the bike . . . makes me incredibly nervous.


that being said, wheels, front end, and everything else looks incredible. nicely done!

Mighty spiffy!

Great project...

Like watching one get built at the factory. Looking good. Did you "hang" some weight with the head steady to lighten the vertical load on the isolastics?

Saber said:

Did you "hang" some weight with the head steady to lighten the vertical load on the isolastics?

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Not on purpose, but I'll look into that.
Thanks for the tips!

RussellTx said:

Not on purpose, but I'll look into that.
Thanks for the tips!

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Definitely add the springs and saddle, (to the head steady) and you'll be right as rain.

That motor is the same as mine. I would disassemble it and rebuild it with new big-end shells and main bearings. None of it is rocket science. Get a workshop manual.

acotrel said:

That motor is the same as mine. I would disassemble it and rebuild it with new big-end shells and main bearings. None of it is rocket science. Get a workshop manual.

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Wow, you’re hardcore. You would strip an engine and replace the big end shells and main bearings immediately after receiving it back from having a professional engine rebuild ??

acotrel said:

That motor is the same as mine. I would disassemble it and rebuild it with new big-end shells and main bearings. None of it is rocket science. Get a workshop manual.

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As FE said - why would you do that to newly rebuilt engine? Watchoo been sniffin' Willis?

Finally getting back on the project again.

I have a 1950's oven I use for powder coating that came in handy for the chain. I really want to save the factory chain if I can but it was super stuck from all the years sitting. I have had it soaking in various fluids for several months and the last step was to heat some gear oil and drop in the chain. I got the oil up to about 350f which is the top end of what the oil can tolerate and dropped it in. It bubbled like the pic below for a couple of minutes - I did not expect that...

The chain was very flexible before it was dipped and shows no wear at all, although I was hoping it would have cleaned up a little better.
Hopefully it will hold up!

I also bought some electrical goodies from Greg so I can build a new harness. I was going to start on that next but decided I needed to get more components in place before I could make much progress. I also have more chrome and polished aluminum bits to shine up which will slow things down again.

I feel like I'm on the down hill side of the project but that's probably wishful thinking...

I'll need to get some help getting it off my (very handy) sketchy table soon!
I at least strapped it down before I hung too much off the back end...

RussellTx said:

I have a 1950's oven I use for powder coating that came in handy for the chain. I really want to save the factory chain if I can but it was super stuck from all the years sitting. I have had it soaking in various fluids for several months and the last step was to heat some gear oil and drop in the chain. I got the oil up to about 350f which is the top end of what the oil can tolerate and dropped it in. It bubbled like the pic below for a couple of minutes - I did not expect that...

The chain was very flexible before it was dipped and shows no wear at all, although I was hoping it would have cleaned up a little better.
Hopefully it will hold up!


View attachment 120339

View attachment 120341

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Chains are so inexpensive, I'm not sure I'd have re-used one on a major project...

Did you measure the chain "sag" when laid out "laying down" on it's outer edges, to see how much "bow" is evident from wear?

Don't do this...

grandpaul said:

Chains are so inexpensive, I'm not sure I'd have re-used one on a major project...

Did you measure the chain "sag" when laid out "laying down" on it's outer edges, to see how much "bow" is evident from wear?

Don't do this...
View attachment 120350

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They were shit when new… compared to newer chains they’re even shitter than that now !!

I used to run Reynolds GP chains, the best you could get, on my T140 back in t’ day… I had to adjust it EVERY RIDE.

I run a Chain Man IWIS on my current T140 and cannot recall when I last adjusted it. The cNw O ring chain on my Commando requires even less !

Fast Eddie said:

They were shit when new… compared to newer chains they’re even shitter than that now !!

I used to run Reynolds GP chains, the best you could get, on my T140 back in t’ day… I had to adjust it EVERY RIDE.

I run a Chain Man IWIS on my current T140 and cannot recall when I last adjusted it. The cNw O ring chain on my Commando requires even less !

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Well, these bits of knowledge are why I post and they are much appreciated, but it usually ends up costing me more $$!!

Is the cNw o-ring the same as the X ring that requires a conversion?

I will alway spend the money on things that are hard to replace later and skimp a little more on stuff that is easier to swap out later. Safety and reliability are exceptions…

Thanks again for the great responses!
They are always very helpful.

RussellTx said:

Well, these bits of knowledge are why I post and they are much appreciated, but it usually ends up costing me more $$!!

Is the cNw o-ring the same as the X ring that requires a conversion?

I will alway spend the money on things that are hard to replace later and skimp a little more on stuff that is easier to swap out later. Safety and reliability are exceptions…

Thanks again for the great responses!
They are always very helpful.

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The cNw kit IS an X ring… not O ring, that was my mistake.

If you’re wanting to limit the dollar damage to your wallet, especially if your sprockets are good, you could get an IWIS chain from this chap. However, I’ve no idea what the logistics time, cost and tariff situation would be these days…

Done with this Commando resurrection yet? Been a few months since your last update, unless your last update was in the for sale section.

Schwany said:

Done with this Commando resurrection yet? Been a few months since your last update, unless your last update was in the for sale section.

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Sorry, It's been slow but steady progress. This is actually good timing as I was going to be posting my completion very soon. I'm currently fighting the cross pipe exhaust alignment but I'm getting there. Having issues with the gap on the kick starter...

After that I'll be ready to take it in to Big D Cycle next week as they want to do the start up since they built the motor.

I think I can get a little more shine on the Original Paint and clean the seat a little better but other than that it is DONE!!!

The first pic is today and the others are from the last month or so.

One other item to note.
I picked up an Ultrasonic Cleaner that worked really well. It holds about 5.5 gallons and is good for small to medium parts.

I tried it with Dawn and Distilled Water for general cleaning and that was ok to get the dirt off but when I loaded it with Evaporust it worked extremely well!
For stubborn rust without the ultrasonic cleaner, I would need to soak items for 24 plus hours and then it would start to hurt the paint in some applications. With the ultrasonic cleaner, I would run it in 5 minute spells and it would be good on even bad rust in 3-4 5 minute runs. For minor rust on bolts or metal parts it was good to go after 5 minutes with some brushing after.

For example, I was able to remove all the rust from the back of the side plate in about 15 minutes.
I think a mouse had homesteaded in there for a bit...

Wish I had started that much earlier in the project.