ZYDECO RACING
______________SERVICES

It's hard to believe, but it's been thirty years now that I've been riding and working on Moto Guzzis. I started with a 1975 850T followed shortly by a 1976 Le Mans which my quite new girlfriend at the time, Loretta, bought for me. We are still together and we still have the LM I. I've had as many as 18 bikes at once(12 of them Moto Guzzis) and mostly Italian. Over the years, I've purchased a couple dealer inventories and collected many bikes and parts. In 2001 I bought Manfred Hecht's inventory from his business, Raceco. In addition to piecing together a full set of factory tools for working on V700 through Daytona/1100 Sport "Big Twin" models, I bought Manfred's special rear drive set up tooling which was developed through his factory contacts and proprietary information from the original manufacturers of the gears. This special tooling not only allows me to shim the crown and pinion gears more quickly(used to take many hours), but much more precisely in both the axial and the radial planes. The precision of this process is further enhanced by custom shims which I use in addition to the factory shims. I also use some other, non factory, special tooling to "load" the crown gear(it is pushed away from the pinion gear in service due to the helical nature of the teeth) to obtain the ideal clearance between the crown and pinion.

Why Just a gearbox and rear drive service? /i//Website_content_2_003.jpg


   Pricing:
           Gearboxes and rear drives are disassembled for cleaning and inspection. All appropriate seals, "O" rings and gaskets are replaced. Gearbox shift return springs  are replaced.
           Rear drives: The pinion gear is removed from it's housing and the bearings are cleaned, inspected and shimmed. Next the pinion is shimmed axially using the "Raceco Rear Drive Set Up Tooling" along with special tooling developed by Zydeco Racing for an ultra precise shimming job. Finally, the crown gear is loaded, as it will be in use, with more special tooling and shimmed radially in relation to the pinion for a perfect running clearance. Often, a copper support ring which holds the
needle roller bearing for the crown in place is badly worn. If this copper ring was to wear through, the bearing would shift off it's race into the inner seal allowing the crown/flange assembly to droop on it's axis with catastrophic results. I have never seen anywhere in print where this part is referenced as a maintenance item or even worthy of inspection. It certainly is both. I replace them constantly. They are cheap.
           I also do a number of gearing swaps for people who want to change their overall drive ratio. Contact me to discuss this.

           Gearboxes: With all the shafts out of the gearbox, the bearings are checked, the layshaft is completely stripped, the mainshaft is checked for separation. If the separation is severe, it will destroy the inner race/locking collar for 5th on the mainshaft and will effectively alter the shimming of the mainshaft causing damage to the engagement dogs on the gear and it's engagement collar(sliding muff). With the layshaft apart the support washer between 2nd and 3rd is checked for wear. If the left handed thread nut on the front of the layshaft inside the box has not been properly torqued, this washer gets "ringed" making the box impossible to shim. All the engagement collar and gear dogs are checked for wear. The layshaft and engagement collars are checked for excessive spline wear. Shift fork wear is also measured. The layshaft is now shimmed to it's assembled working length. Centers are then established for the 1st-2nd and 3rd-4th gear pairings and compared to the centers for the neutral portions of the shift tracks for 1st-2nd and 3rd-4th on your shift drum. What all this mumbo jumbo means is occasionally Moto Guzzi cut the tracks a little off on some of their drums, making precise shimming impossible. If this is the case, I can then go back with custom shims and correct the centers between the gear pairings on the layshaft. Then I readjust the assembled length. Next the mainshaft assembled length is shimmed. Now the shift drum can be shimmed for clearance and then shimmed again front to back in the box to give the proper depth of engagement for the various gear pairings. I now index the eccentric adjuster on the back of the gearbox after setting it for an equal throw on up and down shifts since all of the usual eccentricities have been corrected.
 
 
/i//Website_content_019.jpg

The above described basic services are:
   Rear Drive- $190.00
   Gearbox- $240.00
   Labor Rate- $60.00/Hr. For work done beyond
    the Basic Service procedures.
                    
    

                   
Next Page
There seem to be a number of shops and dealers who offer competent engine services for both stock rebuilds and high performance engine work (None better than my own main sponsor, Mike Rich Motorsports). Also, I don't have the space to take in whole bikes. Few seem to have the interest or expertise to deal with the gearboxes or reardrives. Not only do I do work for several shops, but unfortunately, I do work for bike owners who had shops mess up their GBs & RDs. Even skilled home mechanics would not be able to take on a GB or RD without the necessary factory tools or the ability to make the tools needed.



I have many new and "as new" used parts for MG Standard five speeds. Most new parts are sourced from MG Cycle and sold at their pricing.

Does my five speed gearbox have to clunk into gear when I shift it?

next page


/i//Website_content_2_001.jpg