How to start a cold SSD

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gioto3
Diana
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Location: Ferrara, Italy

How to start a cold SSD

Post by gioto3 » Mon Jul 25, 2011 12:22 pm

I was searching the right way to start from cold my recently acquired 1980 900 SSD. The SD has a choke mechanism near the speedometer that is missing in the SSD. My engine needs some essays before starting from cold and at the moment I don't have any ideas more than try to eliminate air bubbles in the fuel pipes and use the carburettors jiggles.
What is the right way to start the cold engine?
Thanks
Giovanni
1980 Ducati 900 SS Darmah
1977 Ducati 125 six days
1972 Ducati 450 Scrambler
1953 Ducati 65 Sport
1949 Ducati CCC 60

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BevHevSteve
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Post by BevHevSteve » Mon Jul 25, 2011 2:17 pm

turn on the taps
press the 'ticklers' and hold until fuel overflows
twist throttle and hold open for 2 seconds, then close with out slamming
(some bikes need a 2nd throttle twist, some get by with 1 or none)
Gingerly hit starter button and first sign of any backfire RELEASE the button....
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gioto3
Diana
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Post by gioto3 » Mon Jul 25, 2011 10:29 pm

Thanks a lot Steve, I just needed an expert advice!
Ciao from Italy (not far from Borgo Panigale)
Giovanni
1980 Ducati 900 SS Darmah
1977 Ducati 125 six days
1972 Ducati 450 Scrambler
1953 Ducati 65 Sport
1949 Ducati CCC 60

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gioto3
Diana
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Location: Ferrara, Italy

Post by gioto3 » Sun Nov 20, 2011 12:34 pm

Probably it's a stupid question.
This is my first winter with this bike, despite the cold weather, 0-4°C (32-39.2 F), I still want to continue riding.
Utilizing the method suggested by BevHevSteve the engine starts at first essay, but at the beginning of the warm-up after a few seconds of running it backfires quite loudly and regularly, for about 20 seconds, in particular from the vertical cylinder.
After that it runs fine, and once warmed-up it's a beauty.
Is that a normal behavior or I have to worry?
I have 40 Dell'Orto and Conti exhaust.
I presumed it was only a too lean mixture for a cold engine, but today it was really cold and backfires were particularly accentuated and associated to some white smoke form the vertical cylinder exhaust, just for the first 20 seconds.
Thanks in advance
Giovanni
1980 Ducati 900 SS Darmah
1977 Ducati 125 six days
1972 Ducati 450 Scrambler
1953 Ducati 65 Sport
1949 Ducati CCC 60

bobnorton
860 GT / GTS
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Post by bobnorton » Mon Nov 21, 2011 5:20 am

HI, I am not an expert on this motor but it sounds like you are oiling up the plug,probably due to bad valve oil seals, the seals on both cylinders are likely to be shot but the rear cylinder holds the oil round the inlet valve and it can drain into the port while stationry,as the motor warms it begins to move the oil to the plug and miss and bang, then gets hotter and burns away enough to keep running. IF you dont want to strip yet you could try a softer--hotter runing plug but not for fast running as it can overheat the plug and burn piston.A thicker oil 40 monograde will drain slower and may be better than a multigrade.Oiling and rich running will coke up the motor and dirty the oil faster than normal,but if you want to get in a few more rides before winter try the above and carry a spare plug.You could do like the Racing boys and warm up on a soft plug then switch to only one grade softer for ride, Don't wear out the threads use some copaslip on them.

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gioto3
Diana
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Post by gioto3 » Mon Nov 21, 2011 10:19 pm

Hi Bobnorton,
thanks a lot for your precious advice.
I'll strip the heads and change valve seals during winter.
Ciao
Giovanni
1980 Ducati 900 SS Darmah
1977 Ducati 125 six days
1972 Ducati 450 Scrambler
1953 Ducati 65 Sport
1949 Ducati CCC 60

bobnorton
860 GT / GTS
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Location: bromley kent

Post by bobnorton » Tue Nov 22, 2011 1:19 am

Hi Giovanni, To check my thinking you could take out the plug when its missing and banging, if its oil it will be black and a bit shiney.Too rich is matt black, white smoke is oil or water.

wdietz186
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Post by wdietz186 » Tue Nov 22, 2011 1:07 pm

Condition of the valve seals,valves,and adjustment not withstanding keep in mind the 40mm Dellortos were meant for racing and the low speed circuit is pretty crude. Without a proper choke mechanism to richen the mixture,the engine is going to spit and backfire until it reaches running temp. You could try richening the mixture by turning the mixture screws out about 1/4 turn and see how it runs. Just keep track of how much you adjust it so you can readjust it when the weather warms.

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gioto3
Diana
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Post by gioto3 » Tue Nov 22, 2011 1:33 pm

Thanks all.
I'll check the spark plugs and I'll try to richen the mixture too, a too lean mixture for a cold engine was my first thought cause the problem only presented when cold weather arrived. I'll post back the results of my further essays to have your advices.
Thanks again
Giovanni
1980 Ducati 900 SS Darmah
1977 Ducati 125 six days
1972 Ducati 450 Scrambler
1953 Ducati 65 Sport
1949 Ducati CCC 60

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abmartin
SSD900 Darmah
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Post by abmartin » Tue Nov 22, 2011 2:37 pm

gioto3 wrote:Hi Bobnorton,
thanks a lot for your precious advice.
I'll strip the heads and change valve seals during winter.
Ciao
Giovanni
Are there any tricks to easing the valves past the internal O-ring valve seals without damaging them?

Bruce
1979 900SS
Fredericton, NB
Canada

wdietz186
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Post by wdietz186 » Tue Nov 22, 2011 7:22 pm

Make sure there are no sharp edges on the valve at the groove for the retaining rings and use plenty of lube. In addition, install them once!
Pulling the valve out and reinstalling invites tearing the orings. So do your lapping,shimming, etc. beforehand and install the seals at final assembly.

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gioto3
Diana
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Location: Ferrara, Italy

Post by gioto3 » Wed Nov 23, 2011 10:14 am

Today it was a little warmer, about 10°C and I just opened the mixture screw of both carbs of a quarter turn.
Before trying to start I checked the spark plug of the vertical cylinder, that presented a correct aspect.
The engine started at second essay, this time without any backfire or spitting.
Just a little plume of white smoke from the left exhaust for a few seconds.
I didn't care to check again the plug and just went riding without any sign of problems, and I restarted the engine still warm two more times without any smoke from the exhausts.
Now I think the backfires were caused by a too lean mixture in my 40 Dell'ortos for a cold engine and a low external temperature, as also suggested by wdietz186.
Probably the white smoke plume on the left exhaust is caused by a leaking valve seal as suggested bobnorton, but why I don't get the smoke restarting the engine after 15 minutes of stop?
Is it possible to have this behavior with a correctly working vale seal?
Might the oil left on the inlet valve housing of the vertical cylinder just arrive to get into the combustion chamber when the inlet valve is first opened after a prolonged stop?
In any case I think the next time I have to do the valve clearance job I'll strip the heads and change the valve seals, but at this moment I'll keep riding.
Ciao
Giovanni
1980 Ducati 900 SS Darmah
1977 Ducati 125 six days
1972 Ducati 450 Scrambler
1953 Ducati 65 Sport
1949 Ducati CCC 60

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Craig in France
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Post by Craig in France » Wed Nov 23, 2011 10:45 am

gioto3 wrote: ... but why I don't get the smoke restarting the engine after 15 minutes of stop?
It may just be that 15 minutes isn't long enough for enough oil to leak past the seal, Gio.
gioto3 wrote: ... but at this moment I'll keep riding.
Good thinking, not least because getting the rear head off means dropping the engine out of the frame ... >:|!!!

Ciao

Craig

wdietz186
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Post by wdietz186 » Wed Nov 23, 2011 7:20 pm

The white smoke could be steam vapor,caused by cool temp and high humidity. If the smoke dissapates quickly it is likely steam.If it hangs in the air [not rising quickly] it can be oil or oil and gas if a rich start. Unless the plugs are showing signs of oil burning [shiny,oily looking gunk or caked brown/white deposits] and it is consuming less than a qt. per 1000mi. or so I wouldn't worry too much about valve seals etc. If it runs well leave it alone.

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gioto3
Diana
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Location: Ferrara, Italy

Post by gioto3 » Wed Nov 23, 2011 10:49 pm

Craig in France wrote: Good thinking, not least because getting the rear head off means dropping the engine out of the frame ... >:|!!!

Ciao

Craig
Yes I know :cry: If necessary I'll do the job during the rain season !
Ciao

Tanks wdietz186 good point, I hope it could be steam, effectively we had very cold, humid and foggy days here, but today the sun is back. I'll check if this changes something. Moreover I have to say that the aspect of the smoke was different from the oily one, really white and at first it rises a little in the air as a cigarette smoke.
But what is the reason I get the smoke only on the left exhaust?
wdietz186 wrote: If it runs well leave it alone.
Very good suggestion ;) . What works I don't fix.
Ciao
Giovanni
1980 Ducati 900 SS Darmah
1977 Ducati 125 six days
1972 Ducati 450 Scrambler
1953 Ducati 65 Sport
1949 Ducati CCC 60

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