gamezn7 Posted November 13, 2013 Report Share Posted November 13, 2013 So a little bit ago I bought a banshee, the previous owner said that he had some upgrades done to it but he never fully specified everything he replaced, the only thing I noticed right away was an aftermarket Nos cool head. He told me that I could run 93 octane gas on it no problem. BIG MISTAKE. It turns out that my shee was running 18cc cool head domes and with me riding 93 octane my right side completely blew. I initially thought I blew my right cylinder but I took my top end apart and found my right piston in horrible shape, practically melted. My cylinders looked in good shape but anyways I had them re-honed just to be safe. I ordered two new 25mm wsm pistons with new gaskets as well as a pair of 23cc cool head domes. I rebuilt it and she started up just fine, I took her out riding but after a while my right exhaust started spitting. I don't think backfiring would be the proper term here but it sounds like if my right side wants to work but at the same time shut off. I immediately stopped riding it to prevent further damage. My first question is, should I change my carb jets to account for the 23cc domes? And if so what size? Secondly I do notice leaking from my right carb, I fully cleaned both carbs but the leaking on the right one still persists. Could my whole problem be due to a faulty carb or what do you guys think? Quote Link to comment Share on other sites More sharing options...
wayne_smith97 Posted November 13, 2013 Report Share Posted November 13, 2013 Take the carb off and check the float height. 20-22mm. Also use a q tip with toothpaste on it to clean needle seat then make sure the float needle isn't damaged or grooved Quote Link to comment Share on other sites More sharing options...
Jram2088 Posted November 14, 2013 Report Share Posted November 14, 2013 Also check your spark plugs the same thing happened to my bike 1s but on the left side, it would act like it wanted to take off and wanted to work but it would just spit out of the left side, after going over the entire bike i found out it was just a bad spark plug lol the bike was perfect after getting 2 new ones Quote Link to comment Share on other sites More sharing options...
BANSHEE CHAOS Posted November 14, 2013 Report Share Posted November 14, 2013 I remember my old '89 model would do that when it was running low on fuel. Half a twist to RESERVE and it was all good. That one was pretty much completely stock though. TORS and everything still functional... Quote Link to comment Share on other sites More sharing options...
Rustbag Posted November 14, 2013 Report Share Posted November 14, 2013 one step at a time. Do a leak down test - ensure it passes Compression test ensure their within spec with 23cc domes (depending on your elevation if sea level its around 120-130 psi) What doe the plug look like compare both sides. banshee cylinders are 64mm stock. Did you make sure that you used the correct size pistons and that they where within spec of the bore? onto carbs clean them, ensure the float height is properly set. Make sure the needle valve for the float is still in good shape. also make sure their synced so they open and close at the same time. I agree, before you go any further, do a leak down test. You can do a search on how. Quote Link to comment Share on other sites More sharing options...
gamezn7 Posted November 21, 2013 Author Report Share Posted November 21, 2013 Sorry I haven't had time to reply, I've been caught up with school. Thanks for the advice though! I'll make sure to run those tests and see what happens. As for the jets accounting for the 23cc domes, should I order some smaller ones? Quote Link to comment Share on other sites More sharing options...
uman1030 Posted November 21, 2013 Report Share Posted November 21, 2013 Had a similar symptom as you described, ended up being a small tear in the rubber intake boot where the crossover tube goes in. Couldn't even see the tear without applying pressure to the crossover tube. Sent from my Galaxy Nexus using Tapatalk Quote Link to comment Share on other sites More sharing options...
Jereme6655 Posted November 22, 2013 Report Share Posted November 22, 2013 Changing out domes should not require a jetting change. However......who's to say what has been done to your bike has been properly jetted for. Run the tests first, then if she passes and things seem okay then go and clean your carbs and also check your jet size and report back. Quote Link to comment Share on other sites More sharing options...
gamezn7 Posted December 17, 2013 Author Report Share Posted December 17, 2013 Alright guys I ran all the tests and everything seemed to check off. I completely disassembled both carbs and fully cleaned them. I checked the needle valve as well and it still looked brand new, and the float height is within range. I put it back together and it still continues to spit from the right side, I don't know what to do from here. Any other tips? Quote Link to comment Share on other sites More sharing options...
gamezn7 Posted December 19, 2013 Author Report Share Posted December 19, 2013 I did a ohm test on my plug caps and they were at 5k. The spark plugs are brand new and I'm pretty sure I did a leak down test correctly. I even swapped the carbs to see if the left side would have the same problem but it ran just fine so I'm sure the carbs are good. That right side is just weak. If I give it full throttle the left side sounds great with so much power but the right side just won't throw out its potential power, its just extremely weak. Quote Link to comment Share on other sites More sharing options...
Young Guns Racing Posted December 19, 2013 Report Share Posted December 19, 2013 If you are running stock carbs have you ever took them apart to clean them? If not maybe the previous owner did. Anyhow the left carb (one with choke plunger) has a small brass bb pressed into the backside of the carburetor bowl. It has a metering jet inside that bowl to allow flow through that cross tube between ur two carbs. If the bowls are on the wrong carbs - it will run like crap so double check that the bowl with the brass bb in it - viewable from the outside - is on the left carburetor. I had this issue once and chased it til I found out about this. I pass that knowlege on when I can. Quote Link to comment Share on other sites More sharing options...
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