New G5 Project

[Antiquar]

Yesterday I bought a 1979 G5. Indicated ~50,000 miles, but who knows what the real number is.

The old girl is in quite a state, cosmetically.


But most of the important bits and bobs are there. She rolls smooth, with no undue noises. I am able to shift the gearbox through all the gears by hand. Clutch actuation still works. The PO indicates that the engine is not seized and that they were able to start the engine in September. I did not ask them to reproduce this feat for fear of causing unnecessary damage in the attempt.

The right side crash bar bolt is bent, indicating she went down at some point. Thankfully the frame still runs straight. I didn't want those police bars anyway. 

The wiring is a total mess and I will likely have to replace or create a new harness.

I plan to start stripping her down on Saturday. I intend to make her a city and light touring duty bike. Livery still under consideration. I'm going through all the wonderful build and restoration threads here for inspiration. Along with spending a bit of quality time with Guzziology.

[rodekyll]

I might have a less tatty speedo housing and the tach surround for the itty bitty tach that's fed by the cable coming through the steering head.  Also straight fenders and possibly other incidental bits.  PM if interested.

[rtbickel]

That should buff out nicely.

[Antietam Classic Cycle]

Wiring harness(es): http://thisoldtractor.com/for_sale_wiring_harness_tonti_v1000_g5.html

[LeRoy]

You're going go have some good fun. The G5 is one of the best Tonti-framed Guzzi models to begin with. It's a great bike in its own right and may be modified in endless ways or run as a fine stock bike. It also has a clear advantage over things like an 850 T-3 beyond just the bigger displacement. Since it has iron cylinder bores you won't be faced with the flaking chrome bore issue that can be an $800 problem on the 850 T and T-3, as well as other earlier Guzzis. And, you're already money ahead because you have the hard-to-find and expensive original headlight bucket and shell. Mr. Vetter's Windjammer plague didn't apparently victimize your bike. Congratulations!

Would you like a CD containing PDF copies of all of the factory Moto Guzzi G5 documentation (Owners, Workshop and Parts Manuals), as well as copies of period brochures and advertisements, wiring diagrams, helpful hints and illustrated step-by-step engine and transmission rebuild instructions, and much more? If so, just send me a PM with your full name and mailing address and I'll drop one in the mail. No charge.

The same offer applies to all WildGuzzi members. I also have model-specific CDs for the 850 T; 850 T-3; Convert; 1000 SP; California II; California III; 1000S; original Le Mans 850; Lemans II/CX100; Le Mans III; Le Mans 1000 (IV and V); a compilation on the Mille GT_T5_SP2_Strada; a compilation on the V7_Sport-750S-750_S3; and a general but incomplete CD on older small blocks.

Same deal applies to any WildGuzzi member: Send me a PM with your full name and mailing address, the model(s) for which you'd like a CD, and your full mailing address. Free. Shipped worldwide.

[Vince in Milwaukee]

Another great old bike being saved!   

[twowings]

Thanks for saving her! 

[Antiquar]

Thanks, all! This is quite a supportive community. I'm looking forward to keeping this thread up to date with G5 progress.

[troyhamilton]

I had an 850-t which someone had put a convert moter in, it was a very speedy bike. sept isnt long enuff to hurt a Moto Guzzi. And as far as LeRoys cds, they are exceptional!

[wirespokes]

That's great it will return to duty as originally intended. Looks like a really good beginning.

LeRoy - the CD arrived for my new LM 1000, but haven't checked it out yet. Thank you!

[Antiquar]

I spent the better part of today disassembling the bike.



The teardown was thankfully fairly straightforward. There were a few stubborn bots and rods but nothing that could not be coaxed. The oil from all three housings were clean of metal and each had the right smell. There was moly additive in both the rear drive and gearbox. The PO had overfilled the engine--so easy to do on these bikes.


The rear drives still moves nice and smoothly, I may clean it up and use it without a rebuild. If it does begin to leak it is the easiest component to address. The drive shaft, rear drive, and layshaft splines are in serviceable condition. The u-joint and carrier bearing are in remarkable shape, they somehow feel brand new.





The gearbox was in less admirable shape, and seems to have been leaking, at the very least, from the input shaft. The bellhousing REEKED of gear oil and was quite filthy--mostly on the gearbox side. The clutch pushrod still retains the two conical seals (though installed backwards?). Throwout bearing was in good shape. I will have to replace seals on the gearbox at the very least. I have not opened one of these boxes yet, so that will be new territory to me to reach the shift shaft seal and possibly do shimming.





After some scrubbing it's better, but there's much more to do.





I have yet to disassemble the clutch pack for inspection. I am not hopeful it will be in good condition, especially considering the gearbox leak. Obviously I have yet to inspect the rear main flange or cam plug for leaks. I intend to replace the rear main seal, but should I also replace the flange gasket as a matter of course?


Tomorrow I intend to pull the front end, wiring, and brakes from the frame, along possibly clean more parts.



My favorite bit of wiring I saw today:

[azguzzirep]

I loved my G5. Pulled a trailor with it often. The dash lights are terrible. My suggestion would  be to go custom with the speedo and warning lights.

[Antietam Classic Cycle]

The gearbox was in less admirable shape, and seems to have been leaking, at the very least, from the input shaft. The bellhousing REEKED of gear oil and was quite filthy--mostly on the gearbox side. The clutch pushrod still retains the two conical seals (though installed backwards?). Throwout bearing was in good shape. I will have to replace seals on the gearbox at the very least. I have not opened one of these boxes yet, so that will be new territory to me to reach the shift shaft seal and possibly do shimming.

Obviously I have yet to inspect the rear main flange or cam plug for leaks. I intend to replace the rear main seal, but should I also replace the flange gasket as a matter of course?

I've had clutch pushrod leaks with the cone seals no matter which way they're oriented. I use a "stack" of six o-rings now and will send you some for free if you'd like, all I'll need is your address.

I would advise replacing the shift return spring while the transmission is open. There are several very helpful tutorials on the five-speed transmission here: http://www.thisoldtractor.com/guzzitech.dk/gb_en_complex-technical.htm

I would replace the rear main bearing flange gasket (seal the threads of the two lower M8 bolts with Hondabond - they're under the oil level and will seep if you don't), rear main bearing seal, JB Weld the cam plug, replace the breather pipe gasket and replace the crush washers on the oil return line (I like to use a coating of Hondabond on them to make sure they don't leak).

[Groover]

Congrats! I'll def be enjoying this thread. I succesfully restored an '81 G5 a few years ago with lots of help and support from the members on this board.

[Scud]

Great and swift progress. Looking forward to the adventure.

 

[Antiquar]

Thanks all!

Scud, if this project turns out half as well as your Scura refresh I'll be well pleased.

Today I finished stripping bits from the frame and also removed the steering bearings and races. Not too much drama except for a stubborn stanchion. I will say that the PO was a very creative electrician.

Really considering paint options now. Powder coating is ideal, but $$$, especially considering this project needs a good amount of new parts. Might try a pass of Rustoleum and see how it looks before making a final decision.

[Chuck in Indiana]

What? No wire nuts??  I would do just what Charlie sez while you are there. Looks like a great project.. keep up the good work. 

[Scud]

Yeah, powder can be costly. But that frame is going to take a lot of work - and the powdercoater does the sandblasting as part of the price. The paint work I did recently was surprisingly expensive. By the time I bought stripper, primer, and paint I was thinking about what a good deal the powdercoating was - especially factoring in my time. But that's a big frame... could be spendy.

I've been using North County Powdercoating in San Marcos, CA. They give me a little discount if I am willing to wait till they run something else with the same color.

[Kiwi_Roy]

When I did my loop frame I used POR15 paint applied with a brush, it dries out very smooth with no brush marks.
I painted the crash bars and fender stays as well as they were all rusty.
Wear gloves because if you get it on your hands it's there for a week, don't ask me how I know.
Perhaps a new clock from Speedhut
I look forward to following this thread.

[Groover]

For price reference, I paid $400 in 2015 for the frame powder coating on my G5. Included all the frame pieces, swing arm, stands, etc. They sandblasted everything and masked all the areas I wanted masked. Mine was done in Matte Black. I dreaded paying that (the restoration was adding up quickly and exponentially), but in retrospect, I'm glad I did as I don't plan on taking mine down to the frame again. It's pretty resistant to my tool slips, and wipes down pretty easily. I use Meguiar's Quik Detailer (suggested by the powder-coater guy) when I want to clean it up a little more than just a wipe down. I've heard nothing but positive stuff on the POR-15 so that definitely sounds like a good and cheaper option.

Here is a before and after:

[troyhamilton]

I really wished id powdercoated my 850-t a year after i built it i had tones of rock chips on the frame! good automotive paint but not intended for frames!

[Chuck in Indiana]

Powder coat is expensive until you price good 2 part automotive paint.. and.. there is a learning curve to use it, not to mention the safety stuff.

[smdl]

Looking at the cost of POR-15 (which I agree is good stuff) , including the metal prep, base coat and top coat (not to mention brushes, masking materials, sanding/blasting materials, etc.), makes the extra cost associated with powder coating seem more reasonable.  Then there is the reduction in effort to consider...

Personal choice, but I decided to go with powder coating for my frames and associated pieces).

Cheers,
Shaun

[Antiquar]

You pro-powdercoatering guys make some good point. I'll call up some local powdercoaters to get a more informed view of my options. My bank account is still reeling from a big MGCycle order so I may not be thinking straight. 

Perhaps a new clock from Speedhut

That's exactly what I'm thinking. Fab up an aluminum mount for the Speedhut gauges, along with LED idiot lights. I want to integrate those wonderful positive action toggle switches somehow, but serious dash design is a long ways away.

That does mean my relative unmolested headlight bucket and totally trashed dash are free if anyone wants them.

[Groover]

If free means free, I'll take the headlight. If free means available, then depends.  Sent you a PM. I have a spare set of side panels you can have if you need them. They are off a Convert and are pearl white (refinished I believe). They will need blasted.

[Antiquar]

I'm in need of side panels so I am interested. Will respond to your PM.   

[Antiquar]

Does anyone happen to know the dimensions of the rear main bearing flange bolts? M8 x 1.25, but what length? I will want to replace them when I renew the flange gasket. I know to use the wave washers.

Also, since I don't want to buy the $60 bearing puller I plan to use the method detailed here: http://www.thisoldtractor.com/moto_guzzi_loopframe_rear_main_bearing_flange_removal_tool.html

Does the length of the set screws matter? If they are simply there to protect the case threads from the M10 bolts I suppose they just need to sit flush.

I've tried searching but can't find the exact specs.

[Tom H]

Does anyone happen to know the dimensions of the rear main bearing flange bolts? M8 x 1.25, but what length? I will want to replace them when I renew the flange gasket. I know to use the wave washers.

Also, since I don't want to buy the $60 bearing puller I plan to use the method detailed here: http://www.thisoldtractor.com/moto_guzzi_loopframe_rear_main_bearing_flange_removal_tool.html

Does the length of the set screws matter? If they are simply there to protect the case threads from the M10 bolts I suppose they just need to sit flush.

I've tried searching but can't find the exact specs.

The set screws just protect the threads while you screw down the bolts to pull the bearing.

Be careful!!!!!!!!!

My bearing was apperently stuck, the flange cracked while I was CAREFULLY and evenly tightening the bolts to pull it. I thought it was moving, but all that was moving was the flange area the puller bolts were screwed into.

If I have to do one again, I'll try the same way, but also tap it with a hammer and wood punch from the inside.

Good luck,
Tom

[Antietam Classic Cycle]

Does anyone happen to know the dimensions of the rear main bearing flange bolts? M8 x 1.25, but what length? I will want to replace them when I renew the flange gasket. I know to use the wave washers.

Also, since I don't want to buy the $60 bearing puller I plan to use the method detailed here: http://www.thisoldtractor.com/moto_guzzi_loopframe_rear_main_bearing_flange_removal_tool.html

Does the length of the set screws matter? If they are simply there to protect the case threads from the M10 bolts I suppose they just need to sit flush.

I've tried searching but can't find the exact specs.

Bolts are M8-1.25 x 25 grade 8.8. Wave washers should meet DIN 137 spec. I use a low strength thread locker of the six above the oil level: https://www.rockymountainatvmc.com/p/3019/8893/Threebond-Low-Strength-Thread-Locker , on the two below oil level I use Hondabond 4 to seal them.

It might be worth your while to make a puller - a length of steel bar, three bolts, a half hour of time and you're done. Better than buying a new $150 rear main bearing when the "ears" fracture. 

[Antiquar]

Thanks for the specs. I'm going to have nightmares of broken bearing flanges now. Yikes.

I don't know why it never occurred to me to fabricate my own puller. It is a very simple design. hmm.