hey DON,, do you know how to get the fuel to stop foaming in the float bowl????
valin
Active member
Stop the vibration 
The sled hardly vibrates as it sits now, which is surprising. There is no vibration in the running boards whatsoever. I remember my '01 XCR when i put the 90 durometer mounts in it it vibrated immensely. I had to run the harder mounts because I kept breaking mounts. Then I broke the 90's. So, I put a solid torque arm in it. The vibration after that was just plain annoying.
The sled hardly vibrates as it sits now, which is surprising. There is no vibration in the running boards whatsoever. I remember my '01 XCR when i put the 90 durometer mounts in it it vibrated immensely. I had to run the harder mounts because I kept breaking mounts. Then I broke the 90's. So, I put a solid torque arm in it. The vibration after that was just plain annoying.
Valin, what sweep test did you use?, the time duration of the dyno runs?
Also sometimes on the fuel bowl foaming, it comes from the harmonics in the crankshaft as well, the old srx's had this problem. They cured it by adding weight to the flywheel to change the frequency in which the vibration occured and this moved it up higher into the rpm range(past peak rpm) and it also improved the clutch life. harmonics in the crankshaft are very intresting reading, there was a great article in snow tech on this years back from none other then Olav Aaen.
Also sometimes on the fuel bowl foaming, it comes from the harmonics in the crankshaft as well, the old srx's had this problem. They cured it by adding weight to the flywheel to change the frequency in which the vibration occured and this moved it up higher into the rpm range(past peak rpm) and it also improved the clutch life. harmonics in the crankshaft are very intresting reading, there was a great article in snow tech on this years back from none other then Olav Aaen.
bufalobob
Member
softer carb boots &/or tie the carbs together with steel brackets.
click on the link below. this is dynotechs blog page. jim cooper & others have had this problem & were able to correct it with the above techniques.
This time his lectron carbs were tied together with 5 lb of steel brackets. Now fuel flow appears perfect, 140 lb/hr smooth top end fuel to support Jim's 275 CHP. Maybe he can make it down the track next weekend.
http://www.dynotechresearch.com/blog/archives.asp?chosenMonth=10&chosenYear=2007#198
bob
click on the link below. this is dynotechs blog page. jim cooper & others have had this problem & were able to correct it with the above techniques.
This time his lectron carbs were tied together with 5 lb of steel brackets. Now fuel flow appears perfect, 140 lb/hr smooth top end fuel to support Jim's 275 CHP. Maybe he can make it down the track next weekend.
http://www.dynotechresearch.com/blog/archives.asp?chosenMonth=10&chosenYear=2007#198
bob
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valin
Active member
The fuel meter plugs in before the pump, and meters the total amount of flow going to the carburetors. I do not believe I have a foaming issue.
As for time, the runs were probably 5 - 10 minutes apart. The runs were possibly 10 seconds at most in total. It's a Stuska dyno. The sled was hooked up to a cooldown cart the entire time, and pumped continuously.
As for time, the runs were probably 5 - 10 minutes apart. The runs were possibly 10 seconds at most in total. It's a Stuska dyno. The sled was hooked up to a cooldown cart the entire time, and pumped continuously.
toydoc
Member
On old Exciter 570's we use to epoxy lead weight to the carb bowls and add soft boots. Now days we add Fluid Dampers to the flywheels.
toydoc
Member
Nice numbers Valin!
valin
Active member
Thanks toydoc. Hopefully i get it working right early in the year.