750S The Build is Done

[canuck750]

I have been posting up various pics of the progress of the 750S I am starting to work on, going to put the progress here for those that have an interest.

The bike was imported from Germany into Canada a while back, not sure when, the fellow who imported the bike bought a lot of parts from TLM and Stien Dinse way back when and replaced the forks, wheel, brakes, cylinders, crank, bearings, rear drive, shocks, signal lights, switch gear, head and tail light and all the wiring, plus a lot more. The bike was probably salvage from a crash, blow up or both. The steering tube is really bent so I am pretty sure it went down hard once in its life. Tank and tool boxes have been poorly repainted but are rust free and the frame was painted red. It looks Ok from 10 feet away but it is pretty worn out,



Both crash bars are pretty scraped up, the right cylinder has a home made exhaust flange retainer, and the previous owner added funky turn signal indicators to the instrument bezel.



It has a bizarre rear tail light and signal light assembly, not stock



Big ass horn and repro swan necks



850T3 era rear drive



The strip down is not revealing too much I had not expected, other than the bent steering stem, all the bearings are full of dirt and water, seals are shot, hoses are soft, chrome and plating flaking off and all in all a 'Project'.



It all comes apart and gets cleaned, degreased, bead blasted and sorted for painting, zinc plating, chrome and repair or replacement.



Filling a big box of junk



Giladorni cylinders look good,



Charlie supplied a right hand replacement head with good exhaust threads, I found a good set of front and back Borrani rims, cleaned the hubs, replaced the bearings, polished the spokes and nipples and relaced the wheels







Carbs cleaned, parts replaced and rebuilt





Wet sanded the slide faces smooth with 600 grit





Forks have been stripped, tubes are great, dampers are crap, new FAC's and progressive springs will go in after I polish up the lowers.

Swing arm bearings are pitted, the U joint is sloppy, boot is worn out. rear brakes have rock hard shoe surfaces and the internals are full of muck.

Work is going to get real busy this spring so I am aiming to get it all striped, cleaned and boxed to reassemble as time permits. Most of the parts I need have been sourced before the Canadian dollar collapsed under low oil prices so at least I won't break the bank on this one. I have been lucky to find a correct set of rear shocks, head light, signals, swan necks, switch gear, gauges, fuse box, rear drive and all the other little things to make it right.

I had started to accumulate parts to build a tribute from a 850T before this came along so I have an original late V7 tank and original 750S tool boxes already painted in the green stipe scheme.





More to come, slowly I think

[nick949]

It's wonderful that bikes like that end up in your hands Jim. By the time you're finished it will be a real treasure (as long as some wombat doesn't drain it and display it in their living room).

It makes me realize just how lucky I was with mine. I've now put about 20,000kms on it and it continues to run well.

Oh yes - and it's good to see that you hit your thumb too from time to time.  It makes the rest of us feel more human.

Nick

[canuck750]

It's wonderful that bikes like that end up in your hands Jim. By the time you're finished it will be a real treasure (as long as some wombat doesn't drain it and display it in their living room).

It makes me realize just how lucky I was with mine. I've now put about 20,000kms on it and it continues to run well.

Oh yes - and it's good to see that you hit your thumb too from time to time.  It makes the rest of us feel more human.

Nick

Thanks Nick, I think you got one heck of a deal with your 750S!

[motogman]

Oh yes - and it's good to see that you hit your thumb too from time to time.  It makes the rest of us feel more human.

Isn't Jim a dentist (I might be wrong here)?  How do you know that thumb wasn't from a patient biting down?   

really nice work Jim.  I really appreciate your posts.   

[mantaray]

Wow another project ........Yummi   

[canuck750]

Isn't Jim a dentist (I might be wrong here)?  How do you know that thumb wasn't from a patient biting down?   

Not a dentist, the only thing I want to put in a persons mouth is a sock,
Architectural technologist by training, wanabee motorcycle mechanic by passion.

[canuck750]

Pulled the swing arm bearing and races out, but in doing so I pulled the cap right out with the race.



Never had that happen before, oh well knocked the race off with a brass drift and then pressed the cap back into the swing arm.





Pulled the valve gear out, the collets were so frozen on that my spring compressor bent and it took a knock with a brass hammer on the tip of the valve to free the pair of retainers.



Valves look pitted, I got one rebuilt head from Charlie M. and the other one will need new valves, guides and springs.

This poor tight side head is cracked, broken fin, stripped exhaust threads, a big paper weight!

[canuck750]

Progress continues slowly, blasted the rotors clean but they are already at their spec limit. I had another pair that came with a front wheel I picked up but they are the cheaper stamped Brembo discs, not as nice but they will do until I find a set of the forged type.



These have lots of meat left, 6.4mm +/-. off they go to True Disc for grinding



Cleaned up the fork lowers,

I blasted them with crushed glass, then sanded them with 320 grit on a foam backed palm air sander, sanding first saves a lot of time polishing,



I bought a different type of wheel, I think it is called a sizal wheel, cuts real fast and then finish with a buffer wheel and red cutting paste



polished to a satin but not mirror

[O]

I love living vicariously through these build threads (for which I have neither the time nor vocation).  Thanks for taking the time to share the details!

[canuck750]

I love how you just pull everything off a Guzzi and you get left with this, one big lump



And when I pulled the front timing cover I found this,



Aluminum gears on the cam and oil pump, I think the crank gear is an original steel gear. And it looks clean in there.

spun the nuts off the bell housing, dropped the transmission and revealed the flywheel and clutch.



Then filled a pail with cylinders, heads, brake plate, valve covers and the transmission and off to the car wash with a premixed 50/50 solution of aluminum brightener and water, strip off the oxidation in a couple passes. All the aluminum castings need a blast of soda and then a coating of ACF50.



I ran a gallon of paint thinner through the transmission, sloshed it around and then dried it out with air. Next to strip the engine and transmission and measure everything, check bearings etc...

[canuck750]

Stripped the engine today, oil was filthy, like molasses, internals look good but I still need to mic everything. The big end shells look lile they could use replacement.



Crank shaft was replaced in the 90's, should polish up fine, I wish I knew how to identify the cam, I wonder if it is a B10 or not?



Back to the car washer and four soakings with NAPA aluminum brightener, spotless

[nobleswood]

Canuck750,

As someone else posted, I appreciate the tips & pointers, the sisal wheel, the 320 grit on a foam backed disc. All these comments do help the 'not so skilled yet'.

Thanks

[canuck750]

Canuck750,

As someone else posted, I appreciate the tips & pointers, the sisal wheel, the 320 grit on a foam backed disc. All these comments do help the 'not so skilled yet'.

Thanks

I really can't take any credit for the tips, most of them came from the real experts in the community, Mark E, Gregory B, Charlie M, Joe W, Rolf H, the guys at MG Cycle, Harper's, and so many more guys who so freely share their knowledge, the Guzzi community is a great bunch.

[canuck750]

I flat sanded the base of the block and the oil pan (as explained by |Gregory Bender on This Old Tractor web site), brush on engineer's blue dye, glue some 400 grit sand paper to a slab of granite and rotate the block and pan on the sand paper,



It only takes a couple minutes of spinning, sliding the parts with moderate pressure to get a flat surface





I tore down the transmission,





three stuck 6mm bolts, drilled / ground the bolt heads off, the speed drive head is stripped, ground flat surfaces and a big vise grip got it off.



The inside is a sorry mess, grit, grime,





Most of the bearings are sloppy and have a notch in them



Varsol and then an hour in the ultrasonic cleaner



Soda blasted the cases





The transmission will need a bearing set and hopefully the rest of it measures up ok

[John A]

That is some good porn!

[canuck750]

I got to spend a couple hours in the quiet of the garage, seems like not a lot was accomplished by the few pictures I took,

the previous owner covered the cam plug with a soft rubber like caulking that was peeling off. I ran a wire brush over it,, removed all the old goop and mixed up some JB Weld, filled in and should last a lifetime.



I dumped all the cad plated parts on the floor and wore out a fine brass wire wheel on the bench grinder getting everything clean. 2 hours just disappeared. I tie up as much of the small parts as I can with wire and this week I will take the lot in to get cad plated. It's a pretty big box of parts when you add it all up.



The messy and dirty jobs are behind me now for this bike, that is a milestone in my book. I enjoy the reassembly and am glad to be done the cleaning and prep.

Next to prep the small parts for powder coating and ship off the chrome bits that need plating.

[Muzz]

Jim, I am truly in awe at your attention to detail. Your work is an absolute joy to behold!

[balvenie]

I would love to do stuff like that

But I can't so I'll sit here and watch Thanks for posting Jim

[canuck750]

Thanks for the encouragement fellas, tonight I need it

Broke out the micrometers tonight, first off the oil pump, one shaft just on the limit



But the other one is worn, I have a couple of other used ones, hopefully I can find a shaft that is in spec



The cam measures up in tolerance on both bearing ends.

The crank,  both the timing side and flywheel side are past tolerance, this is so disappointing



The pin is OK but the rod shells are worn out and need replacement, so now I need to order a pair of 1st under size bearings and shell out for a crank grind. There goes another $800.00 that I was not planning on.

This now makes four of the early non-oil filter bikes (Eldo, V7 Sport X2, 750S) that the cranks were worn past tolerance, that is what you get when you run flaking chrome bores and dirty oil!!

So for what was advertised as a bike that had a rebuilt drive line I have a worn crank, worn out transmission bearings and a shot U joint, not to mention finished rotors, steering bearings, swing arm bearings etc...... I have no doubt the bike was rebuilt, but that was twenty + years ago and since then some one really flogged this bike. 

I guess this falls under the buyer beware caveat.

[Antietam Classic Cycle]

$164 will buy a new oil pump. Worth every penny after spending all those $$ on crank grinding and bearings.

[canuck750]

$164 will buy a new oil pump. Worth every penny after spending all those $$ on crank grinding and bearings.

Your right Charlie, just need to get over the disappointment of the crank and bearings A new pump will need to be ordered.

[canuck750]

Love your threads Jim 

 Dusty

Thanks Dusty!

This 750S is hell bent on fighting me. I started on replacing the transmission case bearings beginning with removing the races on the end of the shafts. I think its best to match new bearings to new races but I wish I had left these two alone. Two hours to pull two races. Several pullers, heat, grinder and a lot of cursing and the darn things finally came off.

The point of no return, heated races are no longer any use so they have to come off. I managed to get the race to budge just enough to slip this puller under it.



Now this bugger was determined to stay on its shaft. I don't think I have ever had anything so hard to remove.



I had to grind the race flat and cut some grooves in it so the puller would have something to bite on to. Crazy!



I applied some bearing retainer and this factory tool helps get the new race on straight and with little effort.



Two races, one evening, damn!

[SED]

Great thread Canuck!  Love the pictures and the commentary.  I can imagine coming back to it to check how to do everything from polishing fork lowers to removing stubborn bearing races.

You do beautiful work.
Thanks!
Shawn

[Muzz]

I must say again Jim, to see what you do and how you do it is worth it's weight in gold.

Although I am not (at this stage anyway ) in to doing what you do I am certainly learning heaps as to when the time comes. (I have an AG200 Honda out the back ready for when I retire when I find time now that I AM retired.

[canuck750]

Thanks Sed, Muzz,

Guzzis are probably one of the easiest bikes to work on , the motor is simpler than a small block Ford.

Still working on the transmission, HMB sells a kit of bearings for the transmission case. The special shaft bearing is accessed after removing this locking nut, it is reverse thread! There is a punched surface that needs to be pried out of the nut before it will spin off. I use an end off an old U joint to hold the shaft in the vice so I can get the nut off. The Old U joint yoke comes in handy for many transmission jobs to hold the output shaft.



I slipped the new bearing on and a dab of locktite before snugging the nut back on and punching the face into the recess into the shaft.



Now its baking time, I found an old wall oven fro free on Kijiji, its the second one, the first one lost an element after a couple years so I went back on line and found another free one.



I use these bearing drifts to holed the bearing straight and give them a light \tap' to ensure they are fully bottomed



After 20 minutes at 350F and the allloy has expanded so the new race and bearings can drop right in



The bearings drop right in





And before the guts are reassembled two new O rings





This dog is really worn



I found a used one in much better shape (though it too shows wear).

Next to shim the shift drum and then put it back together.

[Muzz]

Looking at your oven Jim reminded me of many years ago when we were first married, my wife opened the oven door when she noticed it was on to find a couple of Matchless crankcases getting a bake. followed. Once she had calmed down some negotiation happened and I was able to end up with a gas welder "for heating". Yes, I know it don't really bake crank cases very well but it is a VERY useful piece of kit and so far I have not needed to bake any others since. (Now where is the fingers crossed emoticon.... )

I have needed to get inside the Breva gearbox twice, which I gather is very unusual, but thanks to a number of members on this site  I have been able to fix it and get it back together again.

[Late to the party]

Dear Canuck 750,

You are my hero. That is all.

Lateness.

[Aaron D.]

Great stuff!

Those timing gears look like the ones I put in my LeMans. They are good. That bike would have had a chain originally.

[canuck750]

Great stuff!

Those timing gears look like the ones I put in my LeMans. They are good. That bike would have had a chain originally.

A chain? Interesting, I would have guessed a gear set but it makes sense now given the alloy gears that are in it. Still no oil filter though, I was hoping to see one when I opened it up.

Ovens are great Muzz, I use it mostly for powder coating. I do my own powder for small stuff, its very cheap and easy to do at home. Eastwood Automotive has a great DIY powder gun and they sell a decent selection of powder, I really only need semi gloss and wrinkle black for what I do (and royal blue for my tools!). I really like how Powder is so mess free, just sweep up the unused powder ad blow off the rest and you only need a couple psi of dry air. I have seem large toaster ovens in use as well for small parts.

Cheers

Jim

[Muzz]

 I have seen large toaster ovens in use as well for small parts.

Cheers

Jim

Never thought of that. A large one could probably hold a crankcase as well.