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Author Topic: Suggested timing curve setting for Dyna 2000, 1025cc  (Read 1053 times)

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Offline gschuld

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Suggested timing curve setting for Dyna 2000, 1025cc
« on: June 11, 2021, 02:41:27 pm »
Ok, next question.  Timing curve for Dyna 2000.

Engine in question:

1025cc for road race application.
CycleX Ported head, 34/28 thin stem valves, beehive springs
New JE 72mm flat top pistons (10.5:1 compression). Great squish band area.
Carrillo rods
MotoGPworks 4/2/1 exhaust
New Keihin CR-31s with 29mm restrictor rings (AHRMA class restriction)
Dyna 2000 ignition with Dyna S pickup
Megacycle 125-75 cam
CycleX ProCut modified (backcut 2/3/4 etc) complete F Model trans

I recall #4 (of 5) being a popular choice, Paul in Australia races a 915cc l/CR-31s road race engine at the #3 setting.

Any thoughts on initial setup is welcome.

As always, thanks in advance

George


« Last Edit: June 11, 2021, 04:39:24 pm by gschuld »
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #1 on: June 11, 2021, 06:00:08 pm »
George, I went with 4 simply because the info that came with it made that one seem the most logical.

Oh, and make sure the 4 pin connector coming from the pick up is snuggly connected to it's mate that goes to the brains. 2 of my pins backed out during connection and left me stranded on the side of I-25. 

Dyno results??
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Offline gschuld

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #2 on: June 11, 2021, 07:40:13 pm »
Quote from: Jerry Rxman Griffin aka MuthaF'er on June 11, 2021, 06:00:08 pm
George, I went with 4 simply because the info that came with it made that one seem the most logical.

Oh, and make sure the 4 pin connector coming from the pick up is snuggly connected to it's mate that goes to the brains. 2 of my pins backed out during connection and left me stranded on the side of I-25. 

Dyno results??

Good points.  Thx.  Dyno session is NEXT Thursday.

George

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Offline Old Scrambler

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #3 on: June 11, 2021, 08:12:07 pm »
Mild compression and de-stroked...................I'd choose #5 and use the retard wire in the upper rpms..........Be ready to play with the trigger setting when on the dyno ;)
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Offline dragracer

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #4 on: June 11, 2021, 11:02:19 pm »
Quote from: Jerry Rxman Griffin aka MuthaF'er on June 11, 2021, 06:00:08 pm
George, I went with 4 simply because the info that came with it made that one seem the most logical.

Oh, and make sure the 4 pin connector coming from the pick up is snuggly connected to it's mate that goes to the brains. 2 of my pins backed out during connection and left me stranded on the side of I-25. 

Dyno results??

I never use that damn connector.  Hard wire it and save yourself a ton of problems.
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Offline PeWe

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #5 on: June 12, 2021, 12:00:18 am »
Interesting read here! ;D
The crank trigger seems to be vital.

Now I see  if full advance happen at or after 3000 rpm is no problem.
My stock advancer with cut springs delay some making low rpm cruising smooth and even.
195-200PSI tested with a cheap compr tester, all 4 cylinders to be equal. Good when comparing cams with different overlap.
Note the numbers that are useful later if something changes.
A sudden 10-25 PSI less helped me to see time for lifting the head, replacing it..
I hope I can stay away from the buy Dyna 2000 now button! ;D
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Offline bear

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #6 on: June 17, 2021, 06:44:07 pm »
Quote from: gschuld on June 11, 2021, 02:41:27 pm
Ok, next question.  Timing curve for Dyna 2000.

I recall #4 (of 5) being a popular choice, Paul in Australia races a 915cc l/CR-31s road race engine at the #3 setting.

Any thoughts on initial setup is welcome.

As always, thanks in advance

George




I would imagine he prefers the flatter curve because he's running methanol.
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Offline Tracksnblades1

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #7 on: June 27, 2021, 05:15:56 am »
Quote from: gschuld on June 11, 2021, 02:41:27 pm
Ok, next question.  Timing curve for Dyna 2000.

Engine in question:

1025cc for road race application.
CycleX Ported head, 34/28 thin stem valves, beehive springs
New JE 72mm flat top pistons (10.5:1 compression). Great squish band area.
Carrillo rods
MotoGPworks 4/2/1 exhaust
New Keihin CR-31s with 29mm restrictor rings (AHRMA class restriction)

Dyna 2000 ignition with Dyna S pickup
Megacycle 125-75 cam
CycleX ProCut modified (backcut 2/3/4 etc) complete F Model trans

I recall #4 (of 5) being a popular choice, Paul in Australia races a 915cc l/CR-31s road race engine at the #3 setting.

Any thoughts on initial setup is welcome.

As always, thanks in advance

George

What length rods did you go with..?
Do you have any Dyno time in..?
« Last Edit: June 27, 2021, 05:22:31 am by Tracksnblades1 »
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Offline gschuld

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Re: Suggested timing curve setting for Dyna 2000, 1025cc
« Reply #8 on: June 27, 2021, 12:56:36 pm »
Quote from: Tracksnblades1 on June 27, 2021, 05:15:56 am
Quote from: gschuld on June 11, 2021, 02:41:27 pm
Ok, next question.  Timing curve for Dyna 2000.

Engine in question:

1025cc for road race application.
CycleX Ported head, 34/28 thin stem valves, beehive springs
New JE 72mm flat top pistons (10.5:1 compression). Great squish band area.
Carrillo rods
MotoGPworks 4/2/1 exhaust
New Keihin CR-31s with 29mm restrictor rings (AHRMA class restriction)

Dyna 2000 ignition with Dyna S pickup
Megacycle 125-75 cam
CycleX ProCut modified (backcut 2/3/4 etc) complete F Model trans

I recall #4 (of 5) being a popular choice, Paul in Australia races a 915cc l/CR-31s road race engine at the #3 setting.

Any thoughts on initial setup is welcome.

As always, thanks in advance

George

What length rods did you go with..?
Do you have any Dyno time in..?

Dyno time turned into a disappointing debacle with no results to show for it

Standard length Carrillos.
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