Picked up the Paso! (includes newbie questions)

[PasoRoo]

Hi All,

After another week of waiting I finally picked up the Paso on Saturday! Rode it home from Sydney (about 280 km of mostly freeway) without any dramas. As most of you already told me, it is a big difference with the Suzuki (thanks to McTool for warning me about the noise, I would have worried all the way home).

While riding it this weekend a few questions came up. I sure that all of this is second nature to Ducati riders, but as I said before I'm new in the Italian camp. OK, here goes:

-The bike has been converted to twin Dell'Ortos. However, it sometimes still stalls when idling, which it does at just below 1000 rpm. If I give it just a little throttle when standing at the lights it is fine. Should the tickover be a bit higher?

-The throttle action is very heavy, is there any way of improving this? If not, I'll probably develop an extremely large and powerful right hand.

-The previous owner has installed a 906 or 7 gearbox (I have been told it uses better bearings?). At low rpm the bike pulls like a train, but it seems to run out of steam a little at higher revs. The highest gear almost seems like an overdrive, or am I just riding it wrong? I go up to the next gear at around 5-6000 rpm. I know it does not have the 100 HP of the GSX (and I am not a svelte Italian, more of a 6'7" North European) but at 140 kph it didn't feel like it would easily power to the theoretical top of 200 something. Or was that last number wishful thinking, even when new in the showroom?

-What sort of revs can it safely pull?I know the redline is at 9000, but at 6000 the bike is making a lot of noise and there is a fair bit of vibration. Or is that where you get to say: Welcome to the world of Ducati!

-I tend to use disc locks for my bikes. They're nice and compact, and any thief would at least have to bring an angle grinder. However, the discs on the Duc don't seem to have a lot of space to stick anything through them. Does anyone have a suggestion of a make or type that would fit? Or are you pretty much limited to cables or chains through the wheel?

Again, I'm a total novice Duc rider so I'm more than happy to take advice from more experienced owners. After all is said and done though, the bike is fantastic fun to ride. The noise out of the 2-1 makes your hair stand on end (try the tunnels in Sydney!), steering is nice and direct and I just love the shape of the bike. I think I'll go and ride it some more tomorrow.

Cheers,

Mike

[paso750]

-I tend to use disc locks for my bikes.

The one I found was for scooters and not for bigger bikes. The locking pin is thinner and fits through the holes of the brake discs.

G.

[ducapaso]

Hi All,

-The bike has been converted to twin Dell'Ortos. However, it sometimes still stalls when idling, which it does at just below 1000 rpm. If I give it just a little throttle when standing at the lights it is fine. Should the tickover be a bit higher?

-The throttle action is very heavy, is there any way of improving this? If not, I'll probably develop an extremely large and powerful right hand.

-The previous owner has installed a 906 or 7 gearbox
Mike

I have no experience with dells, but 100 rpm is a bit too low as an idle for ducs. 1100~1200 should be better;

The dells conversion should require a TOMMASELLI cable kit. Otherwise the trottle Is really hard!

Has your bike a 6 gear box? never seen before! Wonder how the crankshaft fit!

[PasoRoo]

Gerhard,

You were spot on again! Bought a disc lock for a scooter today (actually, I bought two) which fits perfectly through the drilled holes in the discs.

Thanks,

Mike

[whitepaso]

-The bike has been converted to twin Dell'Ortos. However, it sometimes still stalls when idling, which it does at just below 1000 rpm. If I give it just a little throttle when standing at the lights it is fine. Should the tickover be a bit higher?

-The throttle action is very heavy, is there any way of improving this? If not, I'll probably develop an extremely large and powerful right hand.

Mike,

I have twin Dellortos on my 750 and they do have a heavy throttle pull so don't think something is wrong. It comes from the throttle slide return springs inside each carb. Dellorto has 3 rates on these springs; basically light, medium and heavy. I have the light springs and they are heavy so I cannot imagine what the heavy spring feels like. Once you spend some time riding, the pain in your right forearm will go away! Seems to be the nature of the Dellortos; nothing at all like Japanese carbs which have extremely light throttle pull.

This same spring issue is what's causing your idling/stalling issue. Essentially the springs have such force that when you let go of the throttle, the carb slide (which is aluminum on Dellortos) snaps closed and makes a small dent against the idle adjust screw (which is steel). Over time the dent becomes deeper and the idle gets lower until the engine doesn't have enough speed to keep itself running. Simply turn-in your idle screws to get the engine to idle at a higher rpm. I've done it on mine more than once with no issues. It will idle slightly higher when cold and a little lower when hot, so it may take some tweaking until you get the feel of where is best for you. I much prefer to idle higher at a stop and give my right arm muscles a break than having to keep my throttle pulled open a little while sitting there wondering if it will die when I let go of the clutch lever.

When you have the body panels apart to do all this, spend the time to remove the slack from the throttle cables where they enter the carb and at the throttle grip before you adjust the idle screws. Makes a big difference when both slides open at exactly the same time. I suspect you already have the cable splitter so making the adjustments is quite easy.

Lastly, make sure all the hose clamps on the carb connections are very tight to eliminate air intake anywhere. I've found that mine loosen over time from the vibration. If the rubber adapter which connects the carb body to the intake flange on the head is old, you may want to consider replacing them. One excellent source for all the Dellorto parts you'll need is http://www.bevelheaven.com. No affiliation here, just recommending a good source.

Hope this helps.

Tom

[Tamburinifan]

Should be able to rev 9k but since it runs out of breath/power declines
at 7500, no use f revving more.

[jcslocum]

Mike,

Tuning the carbs may help quite a bit. They are a bit finicky tho so check out the threads on tuning in the 750 FAQ.

You need a "Cramp Buster" or "Throttle Rocker" for cruising on the highway. The throttle will kill ya. Try lighter springs. They're not expensive .

[Mc tool]

That gearbox has me intrigued . Far is I know the 906 had bigger berrings ( 62 mm od as opposed to 52mm on the 750 ) which means you would also need the cases ,and the 906 was a 6 speed box with wider gears than the 750 . The 750 is based on the 750 F1 with the rear head reversed , where as the 906 is based on the 851 , so they aint really all that similar
What sort of delorto's pfh or vbh ? and ( as said by ducapaso ) 1100 1200 rpm idle is better . Cleaning and lubing (and check the routing ) of the throttle cables and twist grip can make a big difference . When all the funny noises finally got the better of me , after checking valves ,belts etc I stuck it in neutral and gave it the death rev ( bounced off the rev limiter a couple of times ) and the noises didnt get louder and nothing flew out the side so I figured it was ok and forgot about them ( mostly )
Pleased to hear you both made it home , and long may your hair stand on end

[ducinthebay]

Is there a rev limiter built into the computer?
I certainly have not found it, but the power band tells you shift before you get there.

I have heard of people taking a 6 speed tranny and stuffing it into a 5 speed case. There are some tricks to it, and a seasoned Duck mechanic can help you out with that. I know it can be done, but I can't tell you how.

Cheers,

[PasoRoo]

Thank you all for the advice!
It has certainly put my mind at rest on a few things. I am planning to take the fairings off the bike and have a bit of a closer look. At that stage I should be able to tell which type of Dell'Ortos the bike has, increase the idling revs and check the cables. I would like to master Skins' 'Ducati Cuddle' to try and get the carbs working as well as they can.

Tom, you mentioned the carb slides being snapped back against the idling screw. Is this the cause of the dent in the sliders that people are talking about filing back to a smooth surface?

However, the investigation will have to wait til after this weekend. Monday is a public holiday in Canberra and Massimo (yes, we are those tragic people that name our bikes and cars) gets to go to the coast for the long weekend. The ride to Merimbula is great with plenty of twisty stuff and I can't wait to get to know the red Italian better. I'll start lifting some weights with my right arm in preparation.

Cheers,

Mike

[whitepaso]

Tom, you mentioned the carb slides being snapped back against the idling screw. Is this the cause of the dent in the sliders that people are talking about filing back to a smooth surface?

I'm not sure Mike, but it may very well be. Was that in a thread elsewhere here? I may not have read that. But, now that you asked...when I recently took apart my carbs to thoroughly clean them and install all new gaskets, I noticed the "dent" was a little rough around the edges so I used some very fine emory cloth to remove the roughness on both slides. This worked very good in that the slides moved very freely inside the carb body afterwards.

[Mc tool]

Now who would name their bike ? we may even drink the same beer !
This is a reasult of persistant , and sometimes intermitant noises . The only thing I found was a loose cam pulley on the rear pot .
I fixed my carb slides ( on the guzzi ) by grinding to size , a peice of feeler gauge and glueing it onto the slide ( good prep and devcon liquid steel ) where the idle screw touches the slide This also helped to maintain a constant idle

[higgy]

Think I would have gone with alumalloy in this situation McTool. I have not had a lot of luck with Devcon in high friction uses
And Heh, I've taken bikes down and apart just for something interesting to do for a weekend, Guess I got it real bad............

[Mc tool]

Yeah , I probly should have used something else but I had the devcon ( 60 bucks for a piece of silver cat shit !) but I figured that as the feeler gauge was doing the friction thing , the devcon was really just being an adhesive . I actually bought it to hot up a 5 horse briggs & stratton motor,crudly supercharged , but it kept melting pistons and bending con rods .( you can only swiss cheese a flywheel so much before centrifical force shows itself in a rather obvious way........... never did find all the bits ! ) and yes , pulling things to bits for no good reason is very theraputic

[jcslocum]

Tom, you mentioned the carb slides being snapped back against the idling screw. Is this the cause of the dent in the sliders that people are talking about filing back to a smooth surface? Mike

This info is here: http://forums.ducatipaso.org/viewtopic.php?f=1&t=448