jsekula Posted May 3, 2004 Report Share Posted May 3, 2004 OK, This is interesting... I installed a Digatron unit on my Banshee. I am using two exhaust gas temperature probes. Everything is brand new. The probes are two inches from the end of the exhaust flange. When everything is cold, not running or whatever the air temp is, both probes read exactly the same. BUT, when the engine is running, one runs hotter than the other. About 150-200 degrees difference. Sitting on the bike, the left side cylinder is the hotter one. Any ideas? As for how it runs, very fast. Some other info: I am running a Graydon Proline 2 into 1 intake with one 35mm PWK A/S and a Dynoport 2 into 1 exhaust. Give me your thoughts or expertise... Joe Quote Link to comment Share on other sites More sharing options...
Banchetta Posted May 3, 2004 Report Share Posted May 3, 2004 Check your compression, if that reads the same on both sides, then I'd be looking for an air leak....Do a leak down test...6lbs for 6 seconds. Quote Link to comment Share on other sites More sharing options...
jsekula Posted May 4, 2004 Author Report Share Posted May 4, 2004 (edited) Compression is 127 on each cylinder and no difference in plug color. Edited May 4, 2004 by jsekula Quote Link to comment Share on other sites More sharing options...
Banchetta Posted May 4, 2004 Report Share Posted May 4, 2004 Are you measuring right where the exhaust exits the cylinders? Probe against the pipe? away from the pipe? Quote Link to comment Share on other sites More sharing options...
jsekula Posted May 4, 2004 Author Report Share Posted May 4, 2004 probes are 2" from top of exhaust flange inserted 1" which is 1/4" past center per Digatron. Quote Link to comment Share on other sites More sharing options...
Banchetta Posted May 4, 2004 Report Share Posted May 4, 2004 (edited) I would do a leakdown test....If you have an air leak in the lower end, you might not notice, but would make a huge difference in performance and heat....Have you tried swapping the probes to see if it isn't the probe.... Edited May 4, 2004 by Banchetta Quote Link to comment Share on other sites More sharing options...
jsekula Posted May 4, 2004 Author Report Share Posted May 4, 2004 Bottom end was split and completely redone. The weird thing is when the engine is cooled down to ambient temp, both probes read exactly the same. Quote Link to comment Share on other sites More sharing options...
DUNEDEMON Posted May 4, 2004 Report Share Posted May 4, 2004 Perhaps the scavenging effect of the 2 into 1 pipe is dictating the temp difference? Quote Link to comment Share on other sites More sharing options...
Banchetta Posted May 5, 2004 Report Share Posted May 5, 2004 I would still do a leakdown test...ONce you make a tester, you'll always have it and use it....it'll also give you peace and mind.... Quote Link to comment Share on other sites More sharing options...
jsekula Posted May 6, 2004 Author Report Share Posted May 6, 2004 I would still do a leakdown test...ONce you make a tester, you'll always have it and use it....it'll also give you peace and mind.... Banchetta, I hear you but I am not worried. If I had an air leak, I would see a lean condition on one plug, usually the side the leak is on. Another indication would be hard starting since you would be pulling air through the leak and not a charge through the carb. I spoke with Doug from Digatron who advised this is not uncommon. Here is some data out of the engine... Black is RPMs, Red and Green are cylinder temperatures. This was around the yard three times... The max peaks are 8010 rpms, left cylinder @ 706 degs F and the right @ 380 degs F. The only thing I can come up with is the left cylinder engine case is the stator side which is dry and the right is the clutch which is wet because of the oil bath which should cool that side of the case. It is just a wild guess... Quote Link to comment Share on other sites More sharing options...
DIRTBIKEZ Posted May 6, 2004 Report Share Posted May 6, 2004 left cylinder @ 706 degs F and the right @ 380 degs F. Thats a big difference. I spoke with Doug from Digatron who advised this is not uncommon. Did he have any clue why? Quote Link to comment Share on other sites More sharing options...
Banchetta Posted May 7, 2004 Report Share Posted May 7, 2004 2-300 degrees and not worried.........I would get a second oppinion, mine sais something isn't right Quote Link to comment Share on other sites More sharing options...
jsekula Posted May 7, 2004 Author Report Share Posted May 7, 2004 When talking to Doug, his Harley does the same; the front is cooler than the back. One cylinder is basically leading. In V-8 engines, outer cylinders run cooler and there is no ill effects. Now sure, if your running two carbs on a Banshee, you could tune this out. I am not worried because the way it runs (great). Another thing I noticed with Banshees when pulling the head, one cylinder does run hotter since there is less carbon build up in the dome. Quote Link to comment Share on other sites More sharing options...
Banchetta Posted May 7, 2004 Report Share Posted May 7, 2004 I've used lazer temp guages and got equivilant readings on the cylinders and pipes.....Maybe its a 2 into 1 pipe reason,but I've also got same amount of buildup in my cylinders too........this is abnormal from what I've seen... Quote Link to comment Share on other sites More sharing options...
snowprophet1 Posted May 12, 2004 Report Share Posted May 12, 2004 (edited) Your probes should me more like 7" to 9" from the piston (exhaust side of course) if your 2 into 1 pipes will allow. Your readings will register too low since a lot of unburned gases will be recipricating back and forth that close to the exhaust opening. That won't give you the difference between the two like that though. Try re-checking the grounds for the probes, and if you have the same connectors in the back of the instrument as I do, rotate them a little back and forth to make a good connection. If that doesn't do the trick, switch the two probes (at the instrument first) to see if the gauge is reading incorrectly. If the difference stays on the same probe, switch the probes to the other sides and see what happens. I've used these on my sled and now on my banshee, and have learned a wealth of info from these, especially w/the speed sensor! Awesome gauges! Let me know how you make out. You could actually be scavaging more on one side. Check your reed petals also. ps- how do you move the digatron charts to your posts like that? Edited May 12, 2004 by snowprophet1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.