Top Speed?

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riccorman
Cucciolo - the Lil Pup
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Location: Oklahoma City

Top Speed?

Post by riccorman » Sat Apr 04, 2015 5:13 pm

I read an old forum post somewhere here where a guy said something to the effect of "God help you if you're running a Darmah at 100 mph."

I have a '78 Darmah that I've just put the finishing touches on. I've just put new rubber on and the carbs are synced. She runs like a raped ape. Why not run it at 100 mph? I've been doing just that and not had any problems whatsoever, it runs amazingly well and handles unlike anything I've ever ridden before. But when I get it up to about 90, approaching triple digits, I hear this little old man in my head saying "God help you....." I know she's capable of faster even.. specs say over 114 mph, but at 100 mph that little old man is really screaming at me.

Can anyone give me some objective reasons why I shouldn't run this moto like it was made to? If not, can someone say something to quiet this party-pooper in my head?

Thanks in advance for any/all replies.
-ric
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1978 Ducati 900 SD Darmah
2001 Ducati ST2
2006 Ducati GT1000
2008 Ducati 1098
2015 Ducati Diavel Titanium #196/500

Spagjet
Mach 3
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Re: Top Speed?

Post by Spagjet » Sat Apr 04, 2015 6:15 pm

I've had my GTS (valve spring) bevel up to 220kmh flat out (the speedo needle on the Vague-lia waves madly at that rate but 220 is about the middle of the wave) with a tailwind and patience (then the back carby vibrates off and all of a sudden you're riding a 450 single at warp speed, bad ju ju) quite a few times years ago, not lately admittedly since the world has discovered (and rocked up to) regional Queensland. But the engine has run like a turbine for 20 years since full rebuild and still starts, runs, and revs beauuutiful. A Darmah (desmo) would suck my mirrors off on the way past at that speed (or a LeMans MK111 which always happened, bloody cousins). Point is if a bevel is set up sweet (SWEET- nothing less) and the oil is clean it is truly astonishing what they are capable of. Never heard the 100mph thing, sounds like a crock to me. Bevels are made to rev, they love it. Give it the pills and hang on dude, you only live once,
Brett

riccorman
Cucciolo - the Lil Pup
Posts: 20
Joined: Wed Dec 31, 2014 7:11 am
Location: Oklahoma City

Re: Top Speed?

Post by riccorman » Sat Apr 04, 2015 7:08 pm

THANKS, Brett! This is exactly what I was hoping to hear!
-ric
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1978 Ducati 900 SD Darmah
2001 Ducati ST2
2006 Ducati GT1000
2008 Ducati 1098
2015 Ducati Diavel Titanium #196/500

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Craig in France
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Re: Top Speed?

Post by Craig in France » Sun Apr 05, 2015 2:28 am

riccorman wrote:I read an old forum post somewhere here where a guy said something to the effect of "God help you if you're running a Darmah at 100 mph."
Really? Talking out of his a***, IMO ...
riccorman wrote:Can anyone give me some objective reasons why I shouldn't run this moto like it was made to?
Nope, not me :) . Personally, I'm quite happy running my SSD "like it was made to", to use your expression :-D. (In fact, it's almost an article of faith to see the speedo touch the Magical Ton at least once every time I go out. But let's not broadcast that, eh? 8) ).

Obviously, your running gear needs to be up to the mark: tyres, wheel bearings, head bearing, brakes, suspension etc. But that aside, provided the engine is properly set up and maintained, there's no special reason not to use it's full capacity.

And anyways, don't pay too much attention to the speedo - it's the revs that the engine cares about and that you should be watching. Stick it in first and rev it up to 9,000rpm - now that's what hurts, even if you're only dong 30 mph ... :roll:

riccorman
Cucciolo - the Lil Pup
Posts: 20
Joined: Wed Dec 31, 2014 7:11 am
Location: Oklahoma City

Re: Top Speed?

Post by riccorman » Sun Apr 05, 2015 2:24 pm

Thanks, Craig. In fact, thank you VERY MUCH for your past posts... you have unknowingly helped me solve several problems rebuilding this bike.

Do you happen to have an opinion on the true redline RPM of a Bosch Squarecase (properly warmed up, of course)?

thanks again!
-ric
-ric
-----------------
1978 Ducati 900 SD Darmah
2001 Ducati ST2
2006 Ducati GT1000
2008 Ducati 1098
2015 Ducati Diavel Titanium #196/500

riccorman
Cucciolo - the Lil Pup
Posts: 20
Joined: Wed Dec 31, 2014 7:11 am
Location: Oklahoma City

Re: Top Speed?

Post by riccorman » Sun Apr 05, 2015 2:47 pm

According to the Owners Manual, the speedo is marked redline at 7400 rpm. The text lists max engine rpm at 7800. I've only run mine to about 6200.
-ric
-----------------
1978 Ducati 900 SD Darmah
2001 Ducati ST2
2006 Ducati GT1000
2008 Ducati 1098
2015 Ducati Diavel Titanium #196/500

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Craig in France
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Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Top Speed?

Post by Craig in France » Mon Apr 06, 2015 4:51 am

riccorman wrote:Do you happen to have an opinion on the true redline RPM of a Bosch Squarecase (properly warmed up, of course)?
Ign. Taglioni said 7,800 and that's good enuf for me!

wdietz186
888
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Re: Top Speed?

Post by wdietz186 » Wed May 27, 2015 5:00 pm

Maybe the guy had trouble hanging on at 100 sitting upright. It would get a bit tiring after a while. My old bevel racebike would rev to about 8500 and I hit that with some regularity. I also used to replace the crank and pistons regularly, cases too!

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lomax
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Re: Top Speed?

Post by lomax » Thu Jul 09, 2015 11:55 pm

My 80 Darmah equipped with 40mm carbs and Contis ran 200 km/h (speedometer showing), while a friends 900 Super Light speedo showed 220 km/h then ! It is some years ago, because I do not often move my Ducati anymore, but as far as I remember the rev were at about 8500.
I am sure, that my Darmah is still cabable to reach that speed :-)

Joe
You are in doubt ?......ask a Kraut ;-)
Cheers from Germany
(Ducati 900 SD, Suzuki GSX-R 1000 K6, Suzuki GSX 1200 Inazuma)

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