Author Topic: Possible Dyna 2000 issue??  (Read 2766 times)

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Offline SOHC4 Cafe Racer Fan

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Possible Dyna 2000 issue??
« on: February 23, 2015, 04:05:53 PM »
I use a Dyna 2000 on my CB750.  The following has twice stranded me on my bike:

Bike loses spark and stalls in the middle of crusing at highway speed after about 1.5 hours of riding.  When I restart, the bike revs (with no throttle input) up to about 3500 rpm and then stalls again.  I cannot keep the bike running.  After an extended wait (1 day), the bike fires and runs.  It only happens after a thorough run.

I am wondering if the Dyna box is overheating, although mine is located away from any heat sources with a source of cool air.  No loose wires and plenty of gas.

HAS THIS HAPPENED TO ANYONE ELSE?
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline Retro Rocket

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Re: Possible Dyna 2000 issue??
« Reply #1 on: February 23, 2015, 04:20:57 PM »
The "turning it back on and it revs" is a symptom of fuel starvation, sure your tank breather is all good...?
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline SOHC4 Cafe Racer Fan

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Re: Possible Dyna 2000 issue??
« Reply #2 on: February 23, 2015, 04:23:50 PM »
The "turning it back on and it revs" is a symptom of fuel starvation, sure your tank breather is all good...?

Mick,
That's what Dynatek thought, too.  I'll double check the vent on the cap.  Petcock seems to have no clogs.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline Retro Rocket

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Re: Possible Dyna 2000 issue??
« Reply #3 on: February 23, 2015, 04:44:06 PM »
The "turning it back on and it revs" is a symptom of fuel starvation, sure your tank breather is all good...?

Mick,
That's what Dynatek thought, too.  I'll double check the vent on the cap.  Petcock seems to have no clogs.

Check fuel lines  and filters too mate... ;)
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline SOHC4 Cafe Racer Fan

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Re: Possible Dyna 2000 issue??
« Reply #4 on: February 23, 2015, 04:47:13 PM »
Thanks, Mick. 
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline bwaller

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Re: Possible Dyna 2000 issue??
« Reply #5 on: February 23, 2015, 05:42:26 PM »
What kind of gas tank do you have? When it stalls you might check for fuel in the bowls or pull a plug and check for spark?

It's the crank triggers that overheat. I lost one at a time, twice, that with a slotted ign cover to prevent overheating. Both times the bike would start & idle but break up at about 5500.

Offline scottly

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Re: Possible Dyna 2000 issue??
« Reply #6 on: February 23, 2015, 05:47:51 PM »

Bike loses spark
Usually when Dynas fail, spark is lost on 2 cylinders. Have you verified a loss of spark, or are you guessing that's why the bike died?
Don't fix it if it ain't broke!
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Possible Dyna 2000 issue??
« Reply #7 on: February 23, 2015, 07:42:51 PM »
Mine died on me and I assumed the worse. Turned out that the alternator rotor was not tightened down and spun loose.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline pickle fart

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Re: Possible Dyna 2000 issue??
« Reply #8 on: February 23, 2015, 08:27:33 PM »
Main jet is plugged or partially plugged.

Offline buffalogt750

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Re: Possible Dyna 2000 issue??
« Reply #9 on: February 25, 2015, 05:18:24 AM »
The "turning it back on and it revs" is a symptom of fuel starvation, sure your tank breather is all good...?
It takes an hour and a half of running for a fuel starvation problem to show itself and a full day before it runs right again?
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Offline tweakin

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Re: Possible Dyna 2000 issue??
« Reply #10 on: February 25, 2015, 07:03:07 AM »
What kind of gas tank do you have? When it stalls you might check for fuel in the bowls or pull a plug and check for spark?

It's the crank triggers that overheat. I lost one at a time, twice, that with a slotted ign cover to prevent overheating. Both times the bike would start & idle but break up at about 5500.
I have had the same experience with the 2000.  Added some air vents in the ignition cover on the K1 to hopefully prevent this moving forward.

Offline Retro Rocket

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Re: Possible Dyna 2000 issue??
« Reply #11 on: February 25, 2015, 02:40:09 PM »
The "turning it back on and it revs" is a symptom of fuel starvation, sure your tank breather is all good...?
It takes an hour and a half of running for a fuel starvation problem to show itself and a full day before it runs right again?

It was a suggestion, whats yours...?
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline Spanner 1

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Re: Possible Dyna 2000 issue??
« Reply #12 on: February 25, 2015, 07:43:51 PM »
Run for 1 1/2 hours before fuel starvation ?....... absolutely. Filled the tank on my K8 750 in Cleveland TN heading home to Nashville TN ( 160 miles ). Went for almost 2 hours and the bike died. Thought I had hit reserve, so flipped it over to Res. and it wouldn't start. Opened the gas cap to see how much gas was in there , closed cap bike started right up... rode home the rest of the way no problem ( stock ign., btw )  I figured later that the fuel level dropping from full to close to reserve without the gas cap being opened even once created a vacuum in the tank which eventually stopped fuel flow..... :)
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If your sure it's an ignition problem; it's carbs....