hourmeter/tachometer

[bunboy1]

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

[2001Stroker]

it's probably for a 4-stroke engine

[bunboy1]

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.

[WildShee]

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

[bunboy1]

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.

[bunboy1]

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.

[jamebo]

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?

 

 

[2001Stroker]

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

[LS1Inferno]

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.

[shee rips]

its reading double the actual rpm because banshees fire both plugs twice every revolution.

[bunboy1]

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.

[Bansh-eman]

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

[rubberneck]

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.

[bunboy1]

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

[jbooker82]

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.