Sorry about the length of this post but I feel all the info is required to get my point across and hopefully it will help someone else.
I have been riding, racing, repairing, tuning + modifying, sleds for well over 40 years,[cars, aircraft, bikes+ boats as well, mostly all for personal hobbies + my first orginized race I entered was in 1965 on my Dad's Snow Cruiiser!] The more I learn the more I realize how little I know!
I have read every DCS post in this forum with interest and to gain insight into dealing with this issue on my own sled.
My SRX has had DCS issues since aquiring my Like New , Low Mileage , 2002 SRX a few years back.
Any time I did a long pull or drag race I would get the DCS flash and subsequent performance loss, the sled was like this when it was completely stock. This sled also was what I would call "slow" for what it was.
Porting, reeds, Aaen pipes, heads, clutching, boost bottle,airbox mods, cold air kit ect ect, just added to the problem.
To counter act the problem, I tried numerous things including the following[even when it was stock]:
-checked/cleaned power valves
-checked motor mounts
-I always ran premium fuel blended with 100 LL av gas
-jetted the sled "pig rich"
-tried different head configurations[I have 3 sets of Yamaha heads plus Peak heads with numerous different inserts]
-checked crankshaft phaze/indexing
-ect ect
I had only limited success with every attempt I made to keep the DCS out, but any time the sled would start to make power it would flash the DCS!!!.
Finally I wired in a selector switch with one end to a vibration insulated "dummy" DCS sensor with the other position to the stock mounted DCS sensor and selected between them depending on what I was doing, racing or just riding.
This past summer I removed and installed an engine I had totally rebuilt and included all of the following:
-NEW indexed Viper crankshaft
-ported cylinders
-ported cases
-swain tech coated Stock pistons, new rings, pins + bearings
-NEW stator
-power valves with stainless ends by YA*MA*HEAD
-elliminated boost bottle[as per Valins info]
-got rid of the VForce IIIs + installed Boyeson Rage cages
-added reed spacers
-ect ect
I now have the sled broken in with at least 300 miles on it and have ZERO DCS issues!!!!
LOL ! Yes it is working!
I have jetted the sled down from 157.5s[vents out of box] to 155s[vents in the box] and been running in temps as cold as at -30C/-24F and even when doing a long wide open lake crossing I have not had a single DCS flash!!! All on 91 octane Shell VPower fuel!
The sled has NEVER run so strong, it now pulls like a freight train and Yesterday, on the GPS, ran 107mph/173kph on the hard pack, this is with a high venture windshield, 3" bar rise, hand gaurds, 144"x 1 1/4" ripsaw, boss high rise flat top seat, long travel suspension![obviously not set up for speed!] Its running so well I removed the"Dummy" DCS sensor.
Now to my point! lol ! finally!
I feel due to the age of these sleds the DCS is starting to give problems that are a result of either mechanical problems +/or mechanical wear.
In regards to my 2002 SRX, when I installed the rebuilt engine I also ,fortunately, corrected the DCS issue that this sled was basically suffering from since it was new:
-poor stator output[my hand warmers are operating WAY!!! better since the new stator]
-crankshaft issues...this is what I think was the real problem with this sled. I believe the crank was either out of balance +/or phaze[even though it looked good on a degree wheel] or some other bearing issues that disturbed the engine harmonics.
JM.02c
Hope this helps!
I have been riding, racing, repairing, tuning + modifying, sleds for well over 40 years,[cars, aircraft, bikes+ boats as well, mostly all for personal hobbies + my first orginized race I entered was in 1965 on my Dad's Snow Cruiiser!] The more I learn the more I realize how little I know!
I have read every DCS post in this forum with interest and to gain insight into dealing with this issue on my own sled.
My SRX has had DCS issues since aquiring my Like New , Low Mileage , 2002 SRX a few years back.
Any time I did a long pull or drag race I would get the DCS flash and subsequent performance loss, the sled was like this when it was completely stock. This sled also was what I would call "slow" for what it was.
Porting, reeds, Aaen pipes, heads, clutching, boost bottle,airbox mods, cold air kit ect ect, just added to the problem.
To counter act the problem, I tried numerous things including the following[even when it was stock]:
-checked/cleaned power valves
-checked motor mounts
-I always ran premium fuel blended with 100 LL av gas
-jetted the sled "pig rich"
-tried different head configurations[I have 3 sets of Yamaha heads plus Peak heads with numerous different inserts]
-checked crankshaft phaze/indexing
-ect ect
I had only limited success with every attempt I made to keep the DCS out, but any time the sled would start to make power it would flash the DCS!!!.
Finally I wired in a selector switch with one end to a vibration insulated "dummy" DCS sensor with the other position to the stock mounted DCS sensor and selected between them depending on what I was doing, racing or just riding.
This past summer I removed and installed an engine I had totally rebuilt and included all of the following:
-NEW indexed Viper crankshaft
-ported cylinders
-ported cases
-swain tech coated Stock pistons, new rings, pins + bearings
-NEW stator
-power valves with stainless ends by YA*MA*HEAD
-elliminated boost bottle[as per Valins info]
-got rid of the VForce IIIs + installed Boyeson Rage cages
-added reed spacers
-ect ect
I now have the sled broken in with at least 300 miles on it and have ZERO DCS issues!!!!
LOL ! Yes it is working!
I have jetted the sled down from 157.5s[vents out of box] to 155s[vents in the box] and been running in temps as cold as at -30C/-24F and even when doing a long wide open lake crossing I have not had a single DCS flash!!! All on 91 octane Shell VPower fuel!
The sled has NEVER run so strong, it now pulls like a freight train and Yesterday, on the GPS, ran 107mph/173kph on the hard pack, this is with a high venture windshield, 3" bar rise, hand gaurds, 144"x 1 1/4" ripsaw, boss high rise flat top seat, long travel suspension![obviously not set up for speed!] Its running so well I removed the"Dummy" DCS sensor.
Now to my point! lol ! finally!
I feel due to the age of these sleds the DCS is starting to give problems that are a result of either mechanical problems +/or mechanical wear.
In regards to my 2002 SRX, when I installed the rebuilt engine I also ,fortunately, corrected the DCS issue that this sled was basically suffering from since it was new:
-poor stator output[my hand warmers are operating WAY!!! better since the new stator]
-crankshaft issues...this is what I think was the real problem with this sled. I believe the crank was either out of balance +/or phaze[even though it looked good on a degree wheel] or some other bearing issues that disturbed the engine harmonics.
JM.02c
Hope this helps!
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