US version CX100

[DanPez]

I'm looking at the Lemans II first and second series production bikes information and came up with this:
"The CX 100 version sold in the US - 1000cc with downrated carbs - carried a new frame number sequence beginning at VU11111, with only 353 being made in total "

Would anyone know if all 353 CX100 had Guzzi patented Nigusil-plated cylinders or they were mixed with cast-iron /chrome-plated .......and would have to rely on the engine number VE80390 onwards?

Thanks

Update: Per bible VE80390 onwards was for Le Mans II (850cc) not CX100s

 

[Penis Rotor]

I *think* that the CX100's essentially used the same barrels and pistons as 'Verts and early SP1000's and they were cast iron liners. Not 100% sure though so don't take my word for it.

Pete

 

[Sahms]

The motor in my T3 was originally from a CX, and it did have iron liners.

 

[DanPez]

Just found some info on CX100 in the Le Mans Bible? (Ian Falloon).... apparently the engine # were shared with the SP1000 like you mentioned Pete.
And according to the author ..... out of the 353 CX100 produced 72 of them had the Nigusil-plated cylinders. (from eng# VG215000 and up)

Matching pistons, new rings, lighter, ran cooler, tighter tolerance, improved wear, reduced oil consumption .......but
Is there a huge performance difference between the 2 types of cylinder material?

 

[contractor20]

Viagra like performance Harder for Longer :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:

 

[Moz]

... .......but
Is there a huge performance difference between the 2 types of cylinder material?

its not the performance - the chrome peels in old bikes so they are almost always replaced.

 

[DanPez]

its not the performance - the chrome peels in old bikes so they are almost always replaced.

So if I understand correctly ....your better off getting the Nigusil-plated ?
More or Less when are they in need of replacement the cast iron /chrome? (miles)

 

[Penis Rotor]

As in so many small ways Guzzi were pioneers in using Nicasil as a cylinder liner. Nowadays almost all European, a lot of Japanese and some other bikes all use Nicasil. For several years it was virtually impossible to get Nicasil barrels for older Guzzis because Gillardoni, who make barels for BMW, Aprilia, KTM and a host ol others were just flat-chat doing modern stuff.

Nicasil is *The Biz*. As long as it is looked after it lasts vertually forever, because of the ability o the barells to shed heat more effectively than with a cast irn liner it is VERY, VERY hard to seize a piston unless you're doing something really stupid. As a rough rule of thumb you will get three or four sets of rings through a set of Nicasil bores before they need replacement. There are plenty of 150,000 mile Guzzis around that have never been re-ringed.

Make your own mind up though. If you want wonky old spun cast iron liners simply because they can be re-bored every 50-70,000 miles be my guest. I know what my bikes run.... :mrgreen:

Pete

 

[rolf j]

The nikasil is amazing stuff...and Guzzi was early taking advantage of this development, as it has been said before...:

A short history lesson off Wiki:
"Nikasil is a trademarked electrodeposited lipophilic nickel matrix silicon carbide coating for engine components, mainly piston engine cylinder liners. It was introduced by Mahle in 1967, initially developed to allow rotary engine apex seals (NSU Ro80 and C111) to work directly against the aluminum housing. This coating allowed aluminum cylinders and pistons to work directly against each other with low wear and friction. Unlike other methods, including cast iron cylinder liners, Nikasil allowed very large cylinder bores with tight tolerances and thus allowed existing engine designs to be expanded easily, the aluminium cylinders also gave a much better heat conductivity than cast iron liners, which is an important factor for a high output engine. The coating was further developed by US Chrome Corporation in the USA in the early 1990s (under the trade name of "Nicom"), as a replacement for hard-chrome plated cylinder bores for Mecury Marine Racing, Kohler Engines, and as a repair replacement for factory-chromed snowmobiles, dirt bikes, ATVs, watercraft and automotive V8 liners/bores.
Porsche started using this on the 1970 917 race car, and later on the 1973 911 RS........"

 

[DanPez]

The nikasil is amazing stuff...and Guzzi was early taking advantage of this development, as it has been said before...:
A short history lesson off Wiki:
It was introduced by Mahle in 1967,

I remember using piston rings from this company on an old beemer I had.
Went to the site and saw that they produce all sorts of engine components! (Cylinder liners too)
http://www.mahle.com/C125705E004FDAF9/CurrentBaseLink/W276LG8E707WEBBEN
One could also at 50-70,000 miles, when re-bore is needed, go all the way to insert new liners ..... if taken the bike is vintage!(worth while of course)

 

[Holt]

I'm really not trying to be Mr. Smartass here, but the title caught my attention.
Isn't the CX 100 a motorcycle designed exclusively for the U.S. market? :?:

From the December, 2000 issue of Motorcyclist:

Because of the American belief that there is no substitute for cubic inches, Moto Guzzi replaced the original U.S.-market Le Mans with the CX100 in 1979. The CX featured the larger engine from the sport-touring 1000SP, along with that bike's frame-mounted fairing lowers. The engine may have been larger, but it was also slower; many Guzzi fans felt the CX didn't deserve the "Le Mans" name.

 

[DanPez]

Because of US emission requirements during that time it was downgraded ….. true!

Found some more information on the CX100 specs looking at it from a different point of view. (Source Cycle Magazine 1979)
http://www.motorcyclespecs.co.za/model/moto guzzi/moto_guzzi cx100.htm

Nineteen-eighty's Le Mans shares the same powerplant with the 1000SP: both engines have 948.8cc, achieved by pumping pistons 78mm in 88mm bores. Unlike some Guzzis of the past, the Le Mans does not have chromed aluminum cylinder bores; it has cast-iron liners sunk in finned aluminum shells. The Le Mans' compression ratio is 9.2:1, significantly lower than the 10.2:1 ratio used in the 850 Le Mans.

While the 850 Le Mans had no air cleaners (instead, coarse-mesh-screen rock guards covered the carburetor mouths), the 1000-series Le Mans model has a real airbox and a real air filter. The filter is paper, a throw-away-type, and it rests inside the steel chamber beneath the top frame tubes. The airbox also includes a crankcase rebreather to keep the EPA happy. Even if Guzzi had wanted to supply an engine with rock-guard air cleaners, the intake noise probably would have been prohibitive.

Thirty millimeter Dell' Orto square-slide carburetors are fitted on the V-twin, and they have non-traditional, for Dell' Orto, accelerator pumps built into their needle jet assemblies. When the carburetor needles drop to their closed position they push small pistons down and flood the space above them with gasoline. Next time the slides are opened, the spring-loaded pistons squirt gas through the carburetors' main spray nozzles into the Venturis. This results in instant, clean acceleration from low and high speeds, with satisfactory emission levels during normal cruising. Though the EPA requires emission limits no matter how a bike's carburetor and ignition units are adjusted (which means closely held adjustment limits), the Guzzi has no locks on its carburetor air screws. Presumably most will be cemented in place, similar to those on the Ducati Darmah.

I would guess simple intake mod will bring it up to par?

 

[Sahms]

I would guess simple intake mod will bring it up to par?

No. The compression ratio and valve sizes will still be those of the cooking 949 motor as per SP1000, G5, Convert. The CX also has the full-manhole-lid flywheel. The 850 Le Mans got the half-manhole cover version.

 

[DanPez]

More I read and compared the Le Mans II with the CX100 specs more I agree with Holt's quote from 2000 issue of Motorcyclist !!!

A sale opportunity came up for a CX100 in my area ... doing the research by frame# and engine# .... found out that the bike's simply a pre-79 SP1000 engine with a Le Mans II badge.

The bike looks in excellent condition!





I would have thought that the engine be modified given the Le Mans name ..... but this wasn't the case.
The bike is a beauty! .... but not what I'm looking for.

 

[Lemans]

I would guess simple intake mod will bring it up to par?

No. The compression ratio and valve sizes will still be those of the cooking 949 motor as per SP1000, G5, Convert. The CX also has the full-manhole-lid flywheel. The 850 Le Mans got the half-manhole cover version.

I thought the CX100 had the lighter flywheel?

I understand that the 850 Lemans makes more horsepower. If we were to take compression ratio, and carburation out of the picture, and just speak about the valves... Aren't the large valve heads a 'trade-off'? Meaning that the small valves will produce more power in the lower rpm's, and the large valves produce more power in the higher rpm's. Please correct me, if I'm wrong.

Cheers, AL

 

[Sahms]

I would guess simple intake mod will bring it up to par?

No. The compression ratio and valve sizes will still be those of the cooking 949 motor as per SP1000, G5, Convert. The CX also has the full-manhole-lid flywheel. The 850 Le Mans got the half-manhole cover version.

I thought the CX100 had the lighter flywheel?

I understand that the 850 Lemans makes more horsepower. If we were to take compression ratio, and carburation out of the picture, and just speak about the valves... Aren't the large valve heads a 'trade-off'? Meaning that the small valves will produce more power in the lower rpm's, and the large valves produce more power in the higher rpm's. Please correct me, if I'm wrong.

Cheers, AL

The CX motor I took apart and rebuilt for my T3 had the regular old heavy flywheel, thicker than the one in my LM1 and the same thickness as what's in my Eldo and my SP1000. The small-valve heads may run a little better at lower rpms, but the larger valve heads only came with the higher compression pistons, for a reason. It's the whole package (flywheel, compression, valves and carbs) that makes it run the way it does.

 

[Lemans]

The CX motor I took apart and rebuilt for my T3 had the regular old heavy flywheel, thicker than the one in my LM1 and the same thickness as what's in my Eldo and my SP1000. The small-valve heads may run a little better at lower rpms, but the larger valve heads only came with the higher compression pistons, for a reason. It's the whole package (flywheel, compression, valves and carbs) that makes it run the way it does.

Thanks for the info! I will definitely get my flywheel turned down, on my CX project bike. May also go with larger carbs & K&N's, free flow exhaust, and a mild cam upgrade. Think I'll leave heads & compression alone, as I don't want any issues with pump gas. Do the Lemans 850's run good on premium pump gas?

Cheers, AL