Questions from day 1 on 3CL

V

Various

Junior member
Location
England
I done a bit over 200km on the 3C today to wake it up and noted a few of things, any comments would be appreciated because I don't know what's normal and what's not...

1. Middle cylinder is running richer than the outer cylinders. Middle plug is pretty much black, outer two look text book tan colour.
2. Huge flat spot around 4,000rpm which can be driven through with monstrous amounts of throttle. It seems to be getting better, the general running has improved massively just by riding the bike. The bike speeds up when I back off the throttle at high-ish speed (too rich?)
3. Tickover went up to 1700rpm, then disappeared (would not tick over), then returned at 2,000rpm - now I've slowed it down and it seems very happy.
4. About 20-30minutes after parking up tonight, the engine was still very hot but the oil cooler was stone cold.
5. Rear brake does nothing except give me somewhere to rest my foot.
6. The footrests are different! The left is less offset from the mounting bolt, and the right needs a clown's shoe to reach the gear lever - so I've swapped them over and it seems much better.
7. The top end seems very tappety/rattly sometimes, is this normal? It's running A/11 cams and I'll check the clearances in the morning. Everything looks fine.

Apart from the embarrasingly huge amount of smoke as the oily exhaust cleared itself out, it's been a great day.

Matt


 
1.  Something's not right then...worn carb (slide / needle / needle jet ..... float level .....)
2.  Yes, too rich.  There is the famed 'rich shift' that DellOrto suffers from, but fixing item 1 above will reduce this to an almost unoticeable level
3.  Worn carb spindles makes carb balance problematic & erratic
4.  There's a lot more metal in the engine than your oil cooler!
5.  Should offer some retardation...drum brake set up is important (apparently..I'm disc brakes only  ;) )
6.
7. No, obviously there is some noise from valve gear, but it shouldn't be painfully obvious...or variable
 
1) As per Rob, check the float level though the carbs may need a good cleaning and work through all jets and setting are same for all.
2) As per 1, time to give the carbs a make over... well at least check the float levels etc.
3) Carb balance/again float levels/ air leaks you get the picture
4) Heat sink in the solid lump will take a lot longer to dissipate than that of the oil cooler
5)  Its a Laverda no seriously perhaps the caliper pistons are seized, spin the back wheel, push the pedal and check it that way.
6) Yep normal right one is different curve for the gear lever ( RH change ) and the left to clear the back of the engine when peg is forward
7) Check the clearances yes ... and cam chain adjustment whilst you are at it. 

Smoke yes well my 3C is over 40 so figure can make its own mind up to whether it wants to smoke or not same with the RGS remember that back in the day they never ran exhaust stem seals and the inlets now if the engine aint been open will be as hard as.  Who the hell cares what is happening behind as long as you have a smile on your dial. 
I guess .. at least you know its getting some upper cyl lubrication...sort the carbs out and enjoy it
 
Standard rear disk brake on the 3CL is rubbish. It's a bit of a mystery why Laverda made a cock-up of such a simple system. It can be improved slightly with a bit of modification to the linkage or a smaller diameter master cylinder.

As others have said, basic carb tune is required.
 
You refer to it one time as 3CL and next minute as a 3C.
Which is it?
3C  has spoked wheels and drum rear brake, 3CL has alloy wheels and rear disc.
Drum is usually a better rear brake than the disc.
Some folk have been known to increase jet size on centre cylinder for better 'cooling', not necessary.
Also carbs will benefit from proper clean, new brassware and correct set up.
Sounds like the bike needs servicing too.
Once these are attended to you will have a different bike.
 
You could also check the choke system & make sure the center cylinder choke is closed, seated properly & there is free play on the cable.
 
Agree with Smiddy about the chokes- one thing you can do is pick out the sealing rubbers in the bottom of the choke plungers and turn them over as a quick fix.  Boiling them in water for a few minutes can help restore their shape too.
 
Grant - it's a 3CL (as per the title), just me being lazy when I say 3C.

I checked the valve clearances today and they do need doing, not massively so, but enough. So I'll get that done.

I checked the chokes and while the chokes themselves look fine and the rubbers are seemingly in good condition, there is no free-play at all in the cable system and none available from the adjusters which are fully wound in. Looking into the carb I can see the chokes close the aperture, but I can't tell whether they seat at all. I might drop some new cables on.

Also, there's no air filter so I may as well put one in (my own preference) and work from there.

Thanks for the help so far, much appreciated.
 
I checked the chokes and while the chokes themselves look fine and the rubbers are seemingly in good condition, there is no free-play at all in the cable system and none available from the adjusters which are fully wound in. Looking into the carb I can see the chokes close the aperture, but I can't tell whether they seat at all. I might drop some new cables on.
Click to expand...

No play?  Good place to start there then.
 
Hey various the chokes are small plungers that sit on the side of the carb body I think you may have been looking at the slide in the throttle body.
If you follow the choke cable you will see it goes into a one into three splitter, each cable splits from there to the side of each carbie, if you lift the little rubber boot up you will see a 5mm adjuster tube and locknut nut there should be enough freeplay in that outer cable so you can just loosley lift the cable up and down!!
Goodluck.
 
Hi,

It was the chokes I was looking at, but thanks anyway. Because the adjusters are fully wound in I removed the nut from the adjuster on the middle cylinder and this gave a tiny bit of freeplay. Certainly last night, the bike seemed much improved.

I was wondering whether the cable outer sleeve has been stretched in the past giving the effect of making the cable shorter. It's raining today so I'll take a look.

Thanks.
 
Just buy new choke cables if they are stretched.
Saves a lot of faffing around.
 
The outer sleeve on the single cable from the choke lever is stretched, not sure why all three chokes aren't affected though.

The bike's going off for some work tomorrow so I won't be changing anything soon. I'll just be decorating the house, it had to happen eventually  :o



 
The outer sleeve on the single cable from the choke lever is stretched, not sure why all three chokes aren't affected though.
Click to expand...

Badly made pattern parts probably.  If you're in the UK get Venhill to make 'em up properly.
 
Make sure its sitting all the way in the splitter as this can you some issues. Best to give them all at least an 1/8 inch free play if you can.
If it is sitting in and still an issue simply do as per Cam and cut a bit away... he prefers hacksaw.. me I just wind the outer out a loop or so then with my trusty side cutters lop that bit off.
Whilst your at it check the litle rubbers under the plungers.
Bloody chokes .... RGS aint got any any more .........must remove the reduntant lever at some time now.
 
Given that's it's often likely the choke plungers don't all reseat properly once the choke is released, I've disconnected the plungers from the cables on the centre and RHS carbs. A single choked carb is sufficient to get the bike going until warmed up (not far): I find the choke cable on the LHS carb is easiest to access to ensure correct operation..


AndyW 8)
 
AndyW said:
Given that's it's often likely the choke plungers don't all reseat properly once the choke is released, I've disconnected the plungers from the cables on the centre and RHS carbs. A single choked carb is sufficient to get the bike going until warmed up (not far): I find the choke cable on the LHS carb is easiest to access to ensure correct operation..
AndyW 8)
Click to expand...
Wouldn't have thought a bloke livin in FNQ would need a choke on any cylinder
 
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