1980 Le Mans CX100 looking for info about mods by prior owner

[spiggs]

Hi All.  Just picked up this neglected Le Mans CX100 and the prior owner was an engineer who loved to mod his bikes.  He passed away around 15 years ago so I can't ask the original owner anymore so I am looking for information about the modifications done.  Most interesting are the wheels and brakes.  I have never seen a setup like this.  The wheels are wider than the originals, forks stanchions measure the same as stock but the lowers are custom or had the brake caliper bosses shaved off and replaced by a mounting setup that consists of a plate that floats free of the lower fork leg and is anchored by the strut mounted to a bracket below the triple clamp.  The rear swing arm is chrome plated so may also be non-stock?  Other pictures show the solex carb mod, not sure if this was ever hooked up, and the oil cooler.  So where these common modifications or something fabricated by the prior owner?  Spot anything else odd?  I am sure as I go through this bike other things will pop up.  I think I have almost all the parts for the bike.  From the condition of the fuel tank it looks like the prior owner was in the middle of shaving the emblems off the bike when the project stopped along with the carb install.

Also this is my first Guzzi.  Luckily included with the bike is a pile of shop manuals so I have some guidance to follow.  Where are the good parts sources for these older Guzzi's?

Thanks for the help.

[blackcat]

Wow, I've never seen those kind of modifications. If you have the original parts I'd just put it back together as per the factory and if it were me I'd strip it down to the frame and have it painted or powder coated, new wiring harness from Greg Bender and of course new paint on the tank, etc.  I would also rebuild the engine and open the transmission, etc.

Keep in mind that this model does not usually get much money at resale compared to a LM I so watch what you spend. Unless you plan on keeping the bike, then I'd take the high road.

[spiggs]

I have the stock wheels but not the lower fork legs.  I don't know if those are the original Brembo calipers or not.  Bike came with a spare Brembo caliper of some sort as well.  I don't see any markings on the wheels to know what they are.

If the solex carb was a known good mod I would keep it but if not would stick the stock carbs back on.  I have a feeling it still needs to be jetted and sorted if I were to go down that route.  Bike still has stock exhaust so I don't imagine anything to wild was done to the engine.

The plan is to strip it down to the frame and go through everything.  This will be a fun project for me.  Not planning to ever make my money back, just create a nice Guzzi to ride and show.

[Turin]

I'll take the wheels!
Seriously though, those look like EPM magnesuim wheels. Did the previous owner race this thing? Don't know why it would need an oil cooler. I've never seen floating calipers on a front fork like that. The carb is interesting too.

Really cools guzzi you have there. Someone might know this bike.

[Chuck in Indiana]

What Black cat said. It's not a terribly "desirable" Guzzi, although a nice one. I never have seen a Solex on a Guzzi FWIW.  Normally, if you haven't seen one, there is a reason for that.  I understand that magnesium wheels are too fragile for a street bike.. but maybe an old wife told me that.

[blackcat]

"I don't know if those are the original Brembo calipers or not"

Can't really see what those are but the original Brembo calipers on the CX had dual bleeders.

[Turin]

Maybe he went through all those fork and brake mods to get those EPM wheels to fit? How wide are they?

[guzziart]

Whats with the push-pull rod going from the frame to the rear caliper mounting bracket??!!  So, the bracket moves/pivots on the axle in
unison with the rear frame??  I wonder how well that works as compared to the caliper bracket remaining stationary and moving in unision with the swing arm?  Oh well, interesting complex project for 1st time Guzzista, good luck!

Art

[Antietam Classic Cycle]

Front end mods look like a home-brewed mechanical anti-dive to me, rear looks like a floating caliper setup.

Long intake runners with that Solex setup, might be good for torque, probably hard to get jetting right though.

[spiggs]

Maybe he went through all those fork and brake mods to get those EPM wheels to fit? How wide are they?

Well with the tires mounted can't get the real measurement but the outside front is 3" and the rear 3.5" compared to 2.7" at the same point for the stock rims.  So perhaps a 1/4 inch wider in the front and 3/4 inch wider in the rear.

[spiggs]

Front end mods look like a home-brewed mechanical anti-dive to me, rear looks like a floating caliper setup.

Long intake runners with that Solex setup, might be good for torque, probably hard to get jetting right though.

And unequal length with how the carb is mounted so each cylinder would have a slightly different power curve.

[Turin]

I wonder if there were any engine mods?

[spiggs]

I wonder if there were any engine mods?

Don't know what the ports look like stock but the ones on this engine are really smooth so maybe some port work at least.

[Turin]

looks to me like someone has been in there. Here are some intake pictures from heads I've had done.

small valve Mild porting-



big valve heavy porting

[spiggs]

looks to me like someone has been in there. Here are some intake pictures from heads I've had done.

small valve Mild porting-



big valve heavy porting

I guess with everything else done to the bike it would be odd if the engine was untouched.  The intake port measures 33mm at the inlet, Solex carb is a 36mm.  Exhaust looks stock unless it is parts from a different Guzzi.  Bike came with a number of Solex/Mikuni tuning manuals and a manual for an exhaust gas analyzer but again have no idea what the last running setup was.  Bike also has a spare brand new Solex carb so I could compare the jets in each to see if any tuning was done.  Sounds like the prior owner was going his own way with this setup.  I think my preference though would be to put the stock carbs back on if they would work acceptably with the current setup but of course what I really need to do is tear into the engine and evaluate the rest.

"I don't know if those are the original Brembo calipers or not"

Can't really see what those are but the original Brembo calipers on the CX had dual bleeders.

They are not stock then.  The caliper in the box has dual bleeders.  The ones on the bike have a single bleeder next to the brake line inlet.

[testa_di_formaggio]

What is with the sump? Alt cover? Oil pressure sender? Lots of interesting things to see.

TdF

[faffi]

Will follow the resurrection with interest. If the wheels are indeed magnesium, I personally would be very reluctant to use them since they can become very brittle with time.

[nc43bsa]

The front brake linkage was a popular anti-dive mod in the late 80s, IIRC. 

The rear linkage would be pro-squat, but I've never seen that used before and don't know how effective it would be.

[spiggs]

The front brake linkage was a popular anti-dive mod in the late 80s, IIRC. 

The rear linkage would be pro-squat, but I've never seen that used before and don't know how effective it would be.

Front end mods look like a home-brewed mechanical anti-dive to me, rear looks like a floating caliper setup.
...

Thanks, that makes a lot of sense.  So do you think this was a kit that was available or did the prior owner fab it?

Will follow the resurrection with interest. If the wheels are indeed magnesium, I personally would be very reluctant to use them since they can become very brittle with time.

Yeah I do worry about that.  Looking up EPM wheels brings me to a page that says they were available in magnesium or aluminum.  Any easy way to tell which these are?

[Sye]

Looking up EPM wheels brings me to a page that says they were available in magnesium or aluminum.  Any easy way to tell which these are?

Find a bare bit of the wheel and place a drop of vinager on it. If it bubbles it's magnesium, if not it's aluminium. Rinse well afterwards.

[chuck peterson]

Someone was racing that… mag wheels, oil cooler, anti-dive Earles front fork







Some fotos came thru Facebook lately of Freddie Spencer on a guzzi testing

I’ll go look

[chuck peterson]

On a 1st series le man…

[Turin]

Intake ports would be stock for a small valve head.


Your pic makes me suspect he raised the top of the port.
Mikuni carbs can be a really nice upgrade on a sporting Guzzi. A single dual throat carb is a new one to me, but then again Guzzi went to a single dual throat throttle body on the Quota 1100 and some more recent offerings.

The former owner might have been a genius or a nut job. It might be worth inspecting, refreshing, and running what's there to see how well it works. (especially if you have a brand new carb).
Check those wheels.
I think it would be really cool bike as it sits, especially if it was raced like Chuck is suggesting.

[Turin]

Can you send a pic of the entire bike? 

[acguzzi]

looks like a hollow front axle as well, very interesting, there must also be internal sump mods to accommodate that oil cooler. As for the calipers I think there may have been a mix according to what they had, my rear was twin bleeder my fronts were single bleeder.

[acguzzi]

If it is a race bike I wonder why the discs aren't drilled?

[Turin]

Look at the sump! The fins look really thick and the drain plug is on the left side. What company made that?

There is a lot going on here.

Too cool!

Also, the carb - https://www.mikunipower.com/PHH01.htm Thought it looked like a weber sidedraft.

[AJ Huff]

Do you know who owned the bike? Good chance someone here knew him. I know Mike Tiberio put Mikunis on at least one of his bikes. (As an aside, not implying this was one of Mike's bikes).

-AJ

[spiggs]

Someone was racing that… mag wheels, oil cooler, anti-dive Earles front fork
...

Besides those parts I don't have any info that points to it being raced and in fact a few things that say it wasn't besides maybe track days.  Talking to the daughter of the prior owner she never mentioned racing, it has all the original body work (heavy), no evidence of safety wires on bolt heads etc.

Do you know who owned the bike? Good chance someone here knew him. I know Mike Tiberio put Mikunis on at least one of his bikes. (As an aside, not implying this was one of Mike's bikes).

-AJ

The name George Lieblang is on some of the paperwork I have with the bike.

Look at the sump! The fins look really thick and the drain plug is on the left side. What company made that?

There is a lot going on here.

Too cool!

Also, the carb - https://www.mikunipower.com/PHH01.htm Thought it looked like a weber sidedraft.

Yep, carb is like a mini Weber DCOE.  Mikuni PHH 36 as you found.  A friend of mine had a set of PHH 44 on a Fiat 1300 SOHC engine years ago.  Those were the same size as the DCOE.

Intake ports would be stock for a small valve head.


Your pic makes me suspect he raised the top of the port.
Mikuni carbs can be a really nice upgrade on a sporting Guzzi. A single dual throat carb is a new one to me, but then again Guzzi went to a single dual throat throttle body on the Quota 1100 and some more recent offerings.

The former owner might have been a genius or a nut job. It might be worth inspecting, refreshing, and running what's there to see how well it works. (especially if you have a brand new carb).
Check those wheels.
I think it would be really cool bike as it sits, especially if it was raced like Chuck is suggesting.

Thanks for the measurements.  So a light porting if any.  Former owner worked in aerospace for a number of years then formed his own engineering company.  From what I understand had a long history of modifying motorcycles.  Carb setup reminds me of the Ducati Paso with the single Weber DCNF 44.  Again not sure if it was ever running with the Mikuni PHH.  There is no throttle linkage hooked up and I have not found the rest of the intake manifolds to connect everything together.

[spiggs]

Can you send a pic of the entire bike? 

Here you go.  A bunch of pics of how I got the bike.  Sorry have not had time to give it a first clean up yet.  Hopefully this weekend I can give it a wash and see if I can find any new details.  Really appreciate all the input.