Yeah, well...........

You know all the stories about how CARC final drives are all made of pixie wings and magic seaweed and mere mortals can't take them apart or repair them because we're all as thick as pig dribble..........

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I've had one apart before but while we're effectively shut Michael has been putting this old wives tale to bed. He's working out exactly what we'll need to get made to be able to shim up crownwheels and pinions so we can build good sets into different reactive bridges and refurbish and rebuild them as required.

seriously..you guys should write a book/manual/supplement on the CARC series bikes. Call it CARCalactic or something..
Awesome

I agree, BRAVO! You and Michael are doing something I could never do in my wildest fever dreams.

Awesome stuff, Michael and Pete. Roperology? From Roperville?

I am not surprised one bit. Michael is a clever chap.

Do not share this with the world. Keep it secret squirrel, lest he-who-shall-not-be-named steals it, claims it as his own work, then sells collapsomatic bevel boxes at a horrendous mark-up.




What’s that you say? I’m being cynical? Moi? Never!

Insert it into a volume and sell it via PDF, one that can't be copied...

Thing is at the moment, and likely during my lifetime, being able to rebuild them isn't exactly super-important because, thanks to the flat tappet fiasco, the wreckers are, if not full of, at least populated with, ample CARC bevelboxes from bike's whose engines have departed this vale of tears to the serenade of torched cranks and melted big ends.

This won't always be the case though and in a decade's time I fear that unless someone steps up to the plate the river will run dry and the best series of bikes made by Guzzi in the last 45 years will simply fade away due to a few small and simple pieces being unavailable, the hubris of 'Planned obsolescence' and the de-skilling of the workforce.

Sadly the CARC bikes didn't enjoy the popularity they deserved and didn't sell in the numbers of old loop frames or Tonti's so they won't have that seemingly endless supply of second hand parts that has kept the older models going forever but even those are getting harder to get bits for. I was told yesterday the Guzzi have ceased supply of connecting rod bolts for '70's/'80's motors. So far none of the aftermarket manufacturers have stepped up to the plate and I for one would be a little nervous about beating on an engine with say Stucchi con-rod bolts!🤨.

These are good, solid, machines. It would be a shame for them to disappear from the roads where they so deserve to belong. So? Let's make it happen!

Oz1200Guzzi wrote:

Insert it into a volume and sell it via PDF, one that can't be copied...

Really this wouldn't probably forty years ago been anything unusual and the factory would of provided all the tools and parts to perform tis sort of task.

The problems are twofold. Firstly the lack of skill and understanding of what was something I was taught at tech, namely how to set up a crownwheel and pinion and more importantly the 'Why' it had to be that way. Nowadays there are lots of businesses that specialise in rebuilding car differentials, although they are usually aimed at the 'Performance' market. But very few motorbike specific rebuilders. Since Charley Cole retired I know of no 'Name' in the US who takes on Guzzi rebuilds commercially apart from maybe Charlie Mullendore. Sure there ar still lots of people who probably can and will but I'd have to wonder how many there are under the age of forty?

The closest equivalent to the CARC set up is probably the BMW reactive system. Do they even get rebuilt or are they too a throw away item? Fuck nose!

The second is this obscene idea that a complex and costly component is sacrificial so that people will say "It's buggered. Better throw the vehicle away and get a new one!" With a lot of things I can see that as long as they are recycleable, this philosophy while wasteful is at least theoretically sustainable it is in my opinion shortsighted to claim a totally repairable component isn't repairable simply to move 'New' product.

I dunno? I'm rambling. I'm just not very happy about how the world seems to work any more. Sorry.

I see Harpers has these. Just FYI.
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Interesting. That's a fully disassembled unit. I wonder how much of it is actually new and what its provenance is?

I'm not sure you get "all the bits" in disassembled kit. That same part number shows as "976581 CROWN WHEEL AND PINION ASSEMBLY GREY" or "Moto Guzzi 976581 Bevel gear kit 12/44".

Isn't it just the bevel box sans bearings?

Yeah, I'm a bit puzzled by it all. It does appear from that pic though that the crownwheel spindle is a press fit in the crownwheel itself which is interesting! I thought the entire assembly was one piece. I dunno if our hand press will have enough force! Might have to take it in to the workshop and get the big-guns onto it!

This was the main page description. Kinda looks like the whole shebang.
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Well it's good to know there are parts available. An interesting score as as far as I knew disassembled bridges, with shims etc, were never made publicly available by the factory.

Somebody in Kiwiland had a few CARCs available and advertised one on TradeMe. I was too slow to bid, but would have been willing to pay what the winner bidder offered.

Unfortunately, the seller never came back to offer another one. Perhaps he was expecting a much higher price.

I'd be careful there Dave. The early bikes had an issue with the big bearing that supports the crownwheel in the case. The factory had a recall and sent out new CARC boxes for all bikes. Elsewhere in the world the dodgy boxes were sent back to the factory for bearing replacement. Here and in NZ the tyranny of distance worked in our favour and we as dealerships or service agents got to keep them. Replacing the bad bearing with a good one made a perfectly good brand new unit which, well I at least, put on the shelf 'For later'.

Thing is unless the bearing has been replaced they are potentially lethal! So do take care if buying a 'Brown' bevelbox to ensure it is either off a later bike or has had the bearing replaced.

Pete

Thanks, Pete. I seem to recall the original bearings were made by some sewing machine company???

Polish I believe? Or one of those countries where people wear bones through their noses and use swine as currency.

Interestingly -- well, at least to me -- I have a "spare" (one piece) CARC down in the Moto Grappa. It belongs to Larry LaHue who rode his (nee, my brother's)(rollerized) 2012 8v Norge up here from Florida. He paid $250 for it from Winchester MotoSports!

One of these days, I suppose he'll come to get it, tho it may "disappear" if he forgets about it.

Thanks, Pete & Michael, for that great work on unraveling the mysteries of the "pixie wings and magic seaweed" for us.

Bill

Well after asking Mark Foster who is much better with a lathe and mill than me he called me just now after knocking up this for me.

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So having pushed the bugger apart, (Boy they need a lot of pressure, some heat, and they still let go with a 'BANG' that has everyone in the workshop diving for cover! ) we now have what we need to push the buggers back together.

Next step is to work out the best way to re-install the pinion and as long as your crownwheel and pinion are OK if your CARC bevelbox starts making horrid noises we'll be able to rebuild it completely for a fraction of the cost of a 'New' replacement.

I'll be bolting this one onto my GRiSO and beating on it like a red headed stepchild to test its integrity!

Woohoo!

Almost there. New pinion bearings on and spent ten minutes this morning pulling the pinion nose bearing inner off with a selection of odds and ends from the knife edges box.

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No wonder the are so reliable. That thing is built like a brick shit house.