Rusty rotors, general rehab and cosmetics

[rustyrotor]

Like Luka, I'm working on returning an LM to the road. Mine's a I.

The bike's been outside so the rotors are a bit rusty.
How much rust is too much? Do I wire brush it off or just brake it off?

The diff has leaked fluid onto the 3-4 year old tire's sidewall. Safe? Not?

There are a couple rusty/bubbled spots on tank. What's the quick, simple cheap fix?

Ditto frame. What are some quidelines for determining the solidity of the frame?

The aluminum is dingy throughout. Again, is there a quick, simple, cheap fix?

Many of the fasteners are nasty. Who makes a nice replacement kit?

It's fitted with stainless brake lines. How long do they last? Any maintenance?

All the paint is faded, the bike is an unrestored '78 with a somewhat special drivetrain: Raceco stage II, close-ratio gearbox.

What, if anything else, would you do?

 

[Shane]

Steel wool on the rotors. If pitted heavily, turn them. Minimum thickness is ~5mm I think.
Ditch the tires; you don't know where they have been.
If pits in tank not too bad, fill and paint. Coat the inside of the tank. Otherwise the rust will have to be cut out. A new tank may be cheaper.
If frame is rusted to the point of cutting and welding in new pieces, the rest of the bike is also probably too far gone for a resto. Part it out.
There are only a few special fasteners on the bike, the rest are mostly 8mm, 6mm, 10mm. Do a stock take of what you need and order in bulk through McMaster Carr. I think I have seen s/s fastener kits on fleabay.
Steel wool on the aluminum. Yeah, the tips of your fingers will hate you. Unless heavily pitted, it is cheap to buff to a nice polish.
S/s brake lines should be good. Clean them up with steel wool. Flush the whole system out with brake fluid, replace all seals and crush washers and pistons in the calipers, front and rear. Get the calipers powder coated or electroplated.
If the paint is just faded, I'd just use cutting compound and polish. Lemons look best when the paint is faded.
Buy a new harness from MG Cycle, or rewire it yourself from scratch. The old harness is probably crap. Clean all connectors with steel wool and coat with dielectric grease. You will have fun cleaning the switchgear without breaking anything.
Replace all wheel, swing-arm, driveshaft and steering-head bearings. New cables. Powdercoat the wheels. Polish the plastic to remove any hazing. Ceramic coat the headers and muffler. Replace all fuel lines. Be careful when chemical dipping the carbs. I would advise against bead blasting the carbs. Rebuild carbs with new gaskets. Use common sense when restoring the motor.
Have Chris Cole go through the gearbox and final drive.

If everything is heavily pitted and you want a good looking bike, expect to replace almost everything.

Restoring a Lemon will cost as much as building a replica, and there are 4 times as many Lemons on the road today as produced by the factory. Why stick with a boring, overweight Lemon? Use your money to do something different. My bike had 160,000 miles of grunge on it before I cleaned it up and built the bike I had dreamed of for 20 years.

 

[john zibell]

Rustyrotor,

Shane summed your situation up well. Just an alternate source for common hardware (if you are in the US) is Barnhill bolt. Their web site is: http://www.barnhillbolt.com/ They have alloy, plated and stainless fasteners. I've used them for years with good result.

 

[Lemans]

Thanks for the advise you gave to rustyrotor, as I'm working on a similar project (1979 CX100).

For my rusty rotors, I was going to try an orbital sander. Or could I damage them with that method? I know I wouldn't want to get them too hot.

As for coating the inside of the tank, do you first need to remove rust chemically?

Someone told me that Metal Prep Dip (available at Home Depot) would work well on cleaning up the aluminum. Thought something like that might work nicely along with the steel wool?

Thanks, AL

 

[Shane]

Al,

Personally, I would avoid using a power sander to clean the rotors. My thinking is that you could get a spot too hot, which could warp the rotor. Looking at the picture I see less than 5 minutes work with steel wool to clean it up, and it is a satisfying job. Even better would be to take the rotors (all 3) to your local brake shop and ask them to turn it. The cost should be under $10/rotor.

Tank cleaning and coating. Well, a lot has been said (google gas tank coating). Kreem and POR-15 make tank coating systems, but a lot of people have criticized their products, I suspect more out of poor preparation than anything. I have used Red Kote with good success in a spanish fiberglass tank, which is about as bad as they come. There are companies out there who will cut a hole in the bottom of a motorcycle tank (or cut a car tank in half) just so they can go the extra mile in prepping the surface. As with painting, surface prep is everything.

I'm looking at your wheel with a little concern. Campagnolo casting technology was not well-advanced in the 70s, and their early castings are quite fragile. There seems to be a lot of corrosion on the wheel and depending on how deep it goes, could compromise your wheel strength. Having said that, I have no hard evidence to support this assertion.

As for cleaning aluminum, I just use a nylon pad (magenta color), and nothing else. It's hell on the tips of fingers, but after 30 years, my sand castings have a nice polish and feel very smooth. It's probably not appreciated by those that prefer the look of fresh sand casting or abrasive blasting. I feel that chemicals can be overly aggressive, but they are the weapon of choice for the impatient. I have heard good things said about Honda's S100 for use on sand castings.

 

[Lemans]

Shane wrote:

Al,

Personally, I would avoid using a power sander to clean the rotors. My thinking is that you could get a spot too hot, which could warp the rotor. Looking at the picture I see less than 5 minutes work with steel wool to clean it up, and it is a satisfying job. Even better would be to take the rotors (all 3) to your local brake shop and ask them to turn it. The cost should be under $10/rotor.

Tank cleaning and coating. Well, a lot has been said (google gas tank coating). Kreem and POR-15 make tank coating systems, but a lot of people have criticized their products, I suspect more out of poor preparation than anything. I have used Red Kote with good success in a spanish fiberglass tank, which is about as bad as they come. There are companies out there who will cut a hole in the bottom of a motorcycle tank (or cut a car tank in half) just so they can go the extra mile in prepping the surface. As with painting, surface prep is everything.

I'm looking at your wheel with a little concern. Campagnolo casting technology was not well-advanced in the 70s, and their early castings are quite fragile. There seems to be a lot of corrosion on the wheel and depending on how deep it goes, could compromise your wheel strength. Having said that, I have no hard evidence to support this assertion.

As for cleaning aluminum, I just use a nylon pad (magenta color), and nothing else. It's hell on the tips of fingers, but after 30 years, my sand castings have a nice polish and feel very smooth. It's probably not appreciated by those that prefer the look of fresh sand casting or abrasive blasting. I feel that chemicals can be overly aggressive, but they are the weapon of choice for the impatient. I have heard good things said about Honda's S100 for use on sand castings.

Shane,

Thanks for the sound advice.

I wasn't concerned about the physical condition of the wheels. So I'm glad you gave me a heads up that they may have weakened due to corrosion.

Would you even recommend trying to clean cooling fins with nylon pad?

Thanks, AL

 

[Shane]

Nylon pad on the fins works great; you will have to double-over the pad so that it barely squeezes between the fins and can still move. It won't be concourse perfect, but you would be surprised how much area you can cover (both jugs) in a single evening with a few beers.

 

[Morizzi]

Any rust converter or alloy corrosion cleaner will help. Phosphoric acid is usually the active ingredient.

Use it with the steel wool or nylon scouring pads. It will make the job easier. They will work on both steel and alloy to varying degrees depending on acid content.

You can even try just putting some on an area, leave it for a few minutes. Make sure you rinse off thoroughly after use.

Just the way I do it.

No, the bike doesn't dissolve.

 

[Lemans]

Shane wrote:

Nylon pad on the fins works great; you will have to double-over the pad so that it barely squeezes between the fins and can still move. It won't be concourse perfect, but you would be surprised how much area you can cover (both jugs) in a single evening with a few beers.

Great! And sounds like a fun evening.

I'll see if anyone sells a kit, which comes with all the pads & beers to get the job done:blink:

AL

 

[Sahms]

I wire-wheeled the rotors on my crusty LM. One may be too far gone.

 

[Christofero]

My two cents:

The rotors don't look that rusty - as long as it is surface rust I would just lightly sand them, do some stops and then replace the brake pads. Lemans 1 rotors are hard to get (or at least were) so try to preserve them. I would not get them turned unless there is considerable rust - if they cut off too much metal - which is easy as they are thin to begin with - they will warp pretty much instantly.
The calipers are likely seized - probably best just to replace them with new ones - they aren't that expensive and have the better aluminum pistons.

The tanks are expensive - there is a good trade in them on EBAY (I have seen them at +1000USD) for those who want to make fake Lemons. if you can use the one you have that is good too. You might look at POR 15's tank sealant. I would grind off the rust spots to bare metal and see what you have. If there are holes then find someone good to repair it. Sorry there are no cheap and easy solutions.

By the look of it I would take the frame off and send it and the motor/gearbox for blasting and have the frame powdercoated. Seal the engine before bead blasting or you will regret it. Replace all crappy guzzi fasteners with stainless.

I'm with shane on making a new wiring harness. I actually like the original switchgear but you have to add real grounds (they ground through a tiny wiper that grounds to the handlebars) and it is a good idea to add a small hole on the underside of the switches that allows water out and contact cleaner in. The only problem is that the switchgear is made of plastic that is about as soft as riccotta.

Dielectric grease is good but if judiciously smeared on can cause a short - I use lithium grease for low voltage.

The single best mod that you can make is to fit nicasils - get them while they are still available. Fit K&Ns - velocity stacks are stupid!

The second best is to fit a mitsubishi starter.

Have fun,

ChrisR

 

[Sahms]

Nikasils are available?

 

[rustyrotor]

This forum is the shizzle. I am getting all sorts of useful info.

The exhaust is fixed, the bike is running (more on that in a bit) and fully inspectable IE brakelights, turn sigs, etc.

A few niggles, and a major issue:

It's backfiring, hard, on opening and steady throttle out of one cylinder. I still have not dumped out the 18-month old gas.
The plugs and wires are at least a decade old but look just fine. Really.
There is some preignition in the other cylinder under heavy acceleration.

The batt is toast. Do any of you have the magic code for the elcheapo riding mower battery? Or should I go with a ($) lighter, smaller, gel batt? Either way, who's got the cross ref?

The headlamp reminds me of a Bic being flicked at a Stones concert.
Is there a modern bulb with much greater output that WILL NOT overpower the bone stock, original, harness, altenator, regulator etc.

And the HUGE issue...the integrated brake system is totally marshmallow, the pedal is barely returning, and it's clearly been leaking.
Full rebuild, right? I'm not qualified so will take it to the dealer. Any observations or suggestions? Inexpensive upgrades?

I rode it. Especially with low tire pressure, it is a godawful truck with a riding position dating back to the wooden oval days.
And I love it. I'd been thinking about selling it, and I realized that if I did, I would likely regret it always.

Ride on Guzzisti.

 

[rustyrotor]

Bike on trailer. Will drop at a dealer tomorrow.

Lessons learned (so far):

Batteries are expensive. Take good care of em.
BatteriesPlus here in the US had three different batteries, in stock, that would fit a Lemans (Le Mans? What's that?) though the pricey gel batt is oriented sideways. It'll fit. The batt I bought was rated at 330 CCA and showed almost 500 on the store's meter. Hmmm.

A plain old fine wire brush, small, is a good start with the aluminum. Your hands will hate you.

Scotchbrite (green) does a nice job on the skanky, and amazingly hard corrosion on Staintunes.
You lose the smooth, chromed looking polish, but get a pleasing 'brushed' finish. And it's finally clean.

A decent phillips screwdriver head makes an excellent reamer for getting those old battery connectors to fit the new battery.

Questions:

What gets that old grease and dirt off the engine, without killing everything downstream of my storm drain?

This motor has a 2-plug conversion. the plugs are different sizes, inboard vs outboard, and require 90 degree plug connectors, cables cut to fit. The ones on there now are set up to fit the threaded post on the spark plugs.

How in the heck do you make these things? What's a good source for the bits?
The inboard cables are shorter than the outboards.
Does this matter?

What else?

 

[john zibell]

NGK makes them in 1, 5, and 10 K ohm. Use solid wire leads not resistor type carbon, they don't work well. Relative length doesn't matter.

Descriptions are here: http://www.bikebandit.com/assets/digita ... -Guide.gif

And they may be purchased here: http://www.bikebandit.com/product/16254

or here http://www.denniskirk.com/jsp/product_c ... Id=&mmyId=

 

[Christofero]

From the picture if you drop it at the dealer you will get a bill you wont likely pay..... and the bike won't be reliable.

Really to give the old girl a chance you should take the whole thing apart and restore it to its former glory. If bleeding brakes is too tricky for you I would suggest you buy something with a warranty 'cause this rides going to be fraught with problems - it is a 30+year old italian bike after all.

The easiest way to clean the engine is remove it from the frame and high pressure blast it and then have someone bead blast it. If you don't want to bead blast then high pressure water and detergent and then oven cleaner will clean the oil away but as you say it will do nothing good for the environment - its oil what can you do?

THis is not to discourage you. Guzzi's are one of the easiest machines to work on ever designed. They were designed for the italian military so monobrows from Bergamo can service them. Don't worry it will all be fine once you get stuck in. You will learn a lot and appreciate what Guzzi is really about.

I believe 950 nikasil kits may still be available - check with MG cycle. You can also phone Agostinis in Mandello. They speak english (Alice has a lovely Austrailian accent) and will probably work out cheaper even with shipping.

Replacing/rebuilding the brakes is easy but bleeding the brakes can be a right pain - look for post on the subject in the forum. You should replace the hoses while your at it - aeroquip give a firmer brake.

As to the backfiring - it is difficult to diagnose over the neat but here are the things you might look at:
Exhaust leak
Plugged carb causing lean condition
Intermittent ignition (starting with ignition switch, coils, wires)
Crossfiring due to bad HT leads/Plugs (John's suggestion of NGK is very good - the original Bosch with metal caps are a short looking to happen)
Too much advance

The twin plug is a good mod IMO for the lemans 1.

Handling can be improved by dropping the forks 1" and fitting modern tires. FAC dampers and a fork brace help enormously. No damper is required and check the steering head bearings. Rearsets help the riding position (at least for me). With a tank bag I can just lay down and ride all day without much discomfort.

Getting it to the state you want it to be won't be particularly cheap or quick but like a pair of fine old leather shoes it will fit you and become a joy.

ChrisR

 

[Lemans]

ChrisR,

Although I believe your reply was directed to rustyrotor, him and I are in about the same boat. But I'm sure his is in better condition (Photo was of my project, CX100). So all advice is also appriciated on my end.

In my case, I'm working on a full restoration. Didn't even attempt to start mine, because I want to go through everything first. Hoping to have the upper frame off today. It's been a lot of fun working on her so far. Hoping to complete the job by next Summer.

Thanks, AL