Getting an RGS with a missing spark running

Hi Dan

With a bike that may have been "tuned" by a previous owner, there's a fair chance that someone has changed the jetting. I wouldn't mind betting that it's over-jetted. My suggestion would be to return the carbs to standard spec for your bike. Stock settings for main jets, pilot jets, slides, needles, etc. The standard settings may not be quite right depending on the fuel you have access to, but it's a good starting point to work from. To get it perfect, you should take it to someone with a dynamometer and exhaust gas analyser.

Before you start messing with carbs though, make sure ignition timing and valve clearances are properly set. Also a good idea to check cam timing. You never know what some previous owner may have done (my Jota had the wrong cam sprockets when I bought it - cam timing was way off).

Standard settings for RGS carbs (from factory workshop manual) are:
Dellorto PHF32 DD (x 2, right and centre)
Dellorto PHF32 DS (x 1, left)
Main jet - 108
Idle jet - 65
Needle - K1 2nd notch
Needle jet - 265AB
Slide - 60/6
Mixture screw - 1.5 turns open
Throttle pump jet - 35
Throttle pump capacity - 6.5-7.0 cc in 20 pump cycles
Air filter - replaceable paper element

If you don't have a RGS workshop manual, PM me with your email address and I'll email you a pdf version (43 MB - too big to attach here). I can also send you a Dellorto manual.

Cheers,
Cam
 
It will be too rich on those settings as was for the fuels from back in the day
Should run just fine with 55 pilots, 60/2 slides and 105 mains, and make sure that the float levels are set to between 17.5 to 18.5 as float level has a major bearing on overall carb performance and also again please check the air cleaner.
 
I cannot really see any difference in performance between modern and old fuels, nor in their requirements.  Just that modern fuels tend to go stale a lot quicker, only a matter of weeks sometimes! 

As a starting point, I always return carbs to stock spec when rebuilding a bike, and go from there.  I find a lot of adventurous/ambitious stuff sometimes... carbs are usually also treated to a full rebuild, not just a jet or 2.  It's rarely necessary to deviate far off from stock settings.

piet
 
Hey, thanks again to all. I'd been told and read when I started to think about buying a Ducati or a Laverda that the community of Laverda riders was second to none, and this is proof. Constructive, interested, and informed. So again, thanks.

On the specifics of where I'm going to go next.... I've finally got the bike into the garage I can do work in, which has the sole drawback that it's 100km away. So I have to be patient. I think the fuel thing may be key, so I'll get it back to a state of having a completely drained tank, and put in 5 litres of premium, and see what it does in some controlled riding.

I also thought of the air filter, I believe I have a NOS replacement next time my lovely red girlfriend and I are back together. If not, that replacement is good. And I'll be onto Wolfgang for that and a few other things I already know about (fork seals, rear brake kit [already did front], replace intake manifold, clutch, tires). Some of these things like tires, what's on there is in good shape, with recent replacement, but there are still unknowns, so I'd rather have a known and a backup than just trust what's there.

If that seems to be as reliable and responsive as I hope, then I'll probably give the bike a few more weeks of riding before pulling the carbs out. If it makes it worse, or problems return, I'll pull the bike off the road and get the carbs out and rebuild everything right away, and get it back to factory, per Dellortoman's figures (thanks again, that's great info). I may then play around and see if I can improve on that with some of the variations from factory that were put forward.

The riding season here ends in late October latest, and once that happens, I'll be selectively tackling various bits on the bike to see what I can improve. For now, it's very encouraging that the bike has gone from a sputtering and unreliable mystery to something I've already learned a fair bit about, and starting to pull it apart and put it back together again has been therapeutic.

I must say that, even in this incomplete state, it's a fantastic bike, and I get the Laverda addiction thing.
 
Dan Donaldson said:
Hey, thanks again to all. I'd been told and read when I started to think about buying a Ducati or a Laverda that the community of Laverda riders was second to none, and this is proof. Constructive, interested, and informed. So again, thanks.

On the specifics of where I'm going to go next.... I've finally got the bike into the garage I can do work in, which has the sole drawback that it's 100km away. So I have to be patient. I think the fuel thing may be key, so I'll get it back to a state of having a completely drained tank, and put in 5 litres of premium, and see what it does in some controlled riding.

I also thought of the air filter, I believe I have a NOS replacement next time my lovely red girlfriend and I are back together. If not, that replacement is good. And I'll be onto Wolfgang for that and a few other things I already know about (fork seals, rear brake kit [already did front], replace intake manifold, clutch, tires). Some of these things like tires, what's on there is in good shape, with recent replacement, but there are still unknowns, so I'd rather have a known and a backup than just trust what's there.

If that seems to be as reliable and responsive as I hope, then I'll probably give the bike a few more weeks of riding before pulling the carbs out. If it makes it worse, or problems return, I'll pull the bike off the road and get the carbs out and rebuild everything right away, and get it back to factory, per Dellortoman's figures (thanks again, that's great info). I may then play around and see if I can improve on that with some of the variations from factory that were put forward.

The riding season here ends in late October latest, and once that happens, I'll be selectively tackling various bits on the bike to see what I can improve. For now, it's very encouraging that the bike has gone from a sputtering and unreliable mystery to something I've already learned a fair bit about, and starting to pull it apart and put it back together again has been therapeutic.

I must say that, even in this incomplete state, it's a fantastic bike, and I get the Laverda addiction thing.
Click to expand...

Hi Dan

Cam, Brett, Piet, and Rob are all spot on with the exception of Cam's typo of the 60/6 slides, they are 60/2 as Rob pointed out. A few things to add.

If this bike is a "keeper', and maybe even if it is not, your carb parts list for Wolfgang should include all or most of the following:

three new intake rubbers with new Viton O rings
three new choke plungers (and then learn how to adjust the choke plunger assembly properly)
brand new 60/2 slides if you can handle the cost, the old ones are very likely worn out
the basic rebuild kit, and especially the tiny rubber O rings for the idle mixture adjuster screws
brand new accelerator pump diaphragms
small selection of pilot jets, at least 65/60/and 55 pilot jets, maybe also a 57.5/58 if Wolfgang has them in stock (jets are inexpensive and easy to swap)
brand new K1 needles
brand new AB 265 needle jets
brand new accelerator pump jets, likely around a 35
small selection of main jets, 105, 108, 112, 118, 120 and 122 to try (jets are inexpensive and easy to swap, and I do not know what you are doing for air box derestriction (if any) and exhaust)
brand new cam chain, either from Wolfgang or from Andychain here on this forum

try to get access to a decent ultra sonic unit and also buy some GUNK HydroSeal II to do the initial soak before the ultra sonic cleaning of the bare bodies. Also, obtain a decent set of vacuum gauges for accurate synchronization.

there are some basic things critical to a successful rebuild and set up of an old set of Dellorrto carbs. Do some searches here, then ask any questions, this topic has been covered so many times there is a lot of great information here in past posts.

Don't cheap out on parts or do a half assed job. Also, before you touch the carbs, set the valve clearances accurately, and check and confirm the cam timing and ignition timing with a piston stop, dial indicator and degree wheel, then confirm ignition timing with a timing light. While you are in there and especially if you need to swap valve shims anyways, install and properly tension a new high quality cam chain.

Paul LeClair



 
I have had several RGSs come through the shop over the years and about half of them had the 60/6 slides. All had the normal wear and tear to match the indicated kilometers so I don't think these were swapped out before. My own RGS also had the 60/6s in it. During the rebuild I simply used a set of 60/2s as I had these in stock. 'Dunno how big a difference the pump ramps make as both types seem to work fine.

Tom
 
Interesting and you got me cant even find reference to the /6 ramp wonder what value it is hmmm perhaps for emission's strangled market. Might be interesting to see what is in the Executive next time I get stateside.
Guess at the end of the day don't mean much as usually do away with them which makes the throttle lighter anyways and gives better economy.
 

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The pump ramp doesn't have a great effect in every-day riding.  In fact, the pump volume/action can be reduced considerably before any performance issues crop up.

piet
 
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