bunboy1 Posted May 22, 2008 Report Share Posted May 22, 2008 hi all, i just got done with a complete bottom and top end rebuild. i also purchased an hour/tachometer made by hardline that hooks up to the spark plug wire. according to the tachometer, i am idling at 3,500 rpm + or - 200 rpm. is this accurate? because the maintenance manual says it needs to be 1,450 - 1,550. any thoughts? thanks Quote Link to comment Share on other sites More sharing options...
2001Stroker Posted May 22, 2008 Report Share Posted May 22, 2008 it's probably for a 4-stroke engine Quote Link to comment Share on other sites More sharing options...
bunboy1 Posted May 22, 2008 Author Report Share Posted May 22, 2008 hi there, the box says it is for two or four stroke engines, and it is good for single or multiple cylinder engines. i purchased it from rocky mountain atv. by counting the sparks off the lead, does anyone know how accurate is it? thanks in advance. Quote Link to comment Share on other sites More sharing options...
WildShee Posted May 22, 2008 Report Share Posted May 22, 2008 I have looked into hourmeter/tachometer's before and it always seemed that 2 and 4 stroke part numbers were different. I would look into the documentation or call RMATV and ask them about it Quote Link to comment Share on other sites More sharing options...
bunboy1 Posted May 22, 2008 Author Report Share Posted May 22, 2008 hi there, the box says it is for two or four stroke engines, and it is good for single or multiple cylinder engines. i purchased it from rocky mountain atv. by counting the sparks off the lead, does anyone know how accurate is it? thanks in advance. Quote Link to comment Share on other sites More sharing options...
bunboy1 Posted May 22, 2008 Author Report Share Posted May 22, 2008 hi there, the box says it is for two or four stroke engines, and it is good for single or multiple cylinder engines. i purchased it from rocky mountain atv. by counting the sparks off the lead, does anyone know how accurate is it? thanks in advance. Quote Link to comment Share on other sites More sharing options...
jamebo Posted May 22, 2008 Report Share Posted May 22, 2008 hi all, i just got done with a complete bottom and top end rebuild. i also purchased an hour/tachometer made by hardline that hooks up to the spark plug wire. according to the tachometer, i am idling at 3,500 rpm + or - 200 rpm. is this accurate? because the maintenance manual says it needs to be 1,450 - 1,550. any thoughts? thanks I copied this off one from RMATV, is this it? Quote Link to comment Share on other sites More sharing options...
2001Stroker Posted May 23, 2008 Report Share Posted May 23, 2008 A 2-stroke fires on EVERY revolution. 4-strokes fire on every other revolution. Which is why your tach is reading twice the RPM that it is actually firing. The product that you bought is obviously not for 2-strokes. Here's one on eBay that is specifically for 2-strokes. The title says for 2 or 4 strokes, but read the description. This one is made for 2 or 4 strokes that fire on every revolution. He also sells them for engines that fire every other revolution. You need this one, right here. http://cgi.ebay.com/ebaymotors/NEW-TACHOME...8QQcmdZViewItem Quote Link to comment Share on other sites More sharing options...
LS1Inferno Posted May 23, 2008 Report Share Posted May 23, 2008 I bet theres some thing to change for a two stroke becuae you still have two sparkes per cycle but there are two less strokes in the cycle. just remember its half. Quote Link to comment Share on other sites More sharing options...
shee rips Posted May 23, 2008 Report Share Posted May 23, 2008 its reading double the actual rpm because banshees fire both plugs twice every revolution. Quote Link to comment Share on other sites More sharing options...
bunboy1 Posted May 23, 2008 Author Report Share Posted May 23, 2008 i only wrapped the wire over one ignition lead. should it count every spark on that cylinder only? how about the hour meter? would that be off as well? thanks. Quote Link to comment Share on other sites More sharing options...
Bansh-eman Posted May 23, 2008 Report Share Posted May 23, 2008 it is showing double becasue the banshee ignition fires both plugs at the same time. it does not fire back and forth. so for one cylinder it will fire at TDC and BDC, this is in turn giving you double the rpm for that cylinder Quote Link to comment Share on other sites More sharing options...
rubberneck Posted May 23, 2008 Report Share Posted May 23, 2008 it is showing double becasue the banshee ignition fires both plugs at the same time. it does not fire back and forth. so for one cylinder it will fire at TDC and BDC, this is in turn giving you double the rpm for that cylinder Yep, this is exactly correct. Each plug on our motors fires twice every rpm.. when i set up my vapor, i had to account for this. Quote Link to comment Share on other sites More sharing options...
bunboy1 Posted May 28, 2008 Author Report Share Posted May 28, 2008 ok i want to buy another tach/hour meter. so what do you guys think i need to buy. a 1 spark 1 rpm, or a 2 sparks per rpm? please let me know. thanks Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted May 28, 2008 Report Share Posted May 28, 2008 2 sparks per 1 rpm. Why not just use the one you have. Those tachs arent ment to be used to tell what rpm your at while riding. They are too small. Try focusing on the small tach while doing a WOT run. They are ment for checking Idle speed. All you have to do is read the RPM it is showing and divide by 2. Quote Link to comment Share on other sites More sharing options...
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