Ducati Monster Forum

Moto Board => Tech => Topic started by: memper on November 04, 2012, 12:11:29 PM

Title: Anyone know tach ratios?
Post by: memper on November 04, 2012, 12:11:29 PM
Im looking to put an electric (not digital) aftermarket mini tach on my bike. What ratio should I look out for? Im seeing mostly 1:2 on ebay but my intuition is telling me that this is not suitable. Ideas?

('99 750)
Title: Re: Anyone know tach ratios?
Post by: motoxmann on November 04, 2012, 02:37:44 PM
the carbed engines trigger spark every revolution (wasted spark), not only on compression stroke. so you'd want a 1:1 tach, aka 1 trigger = 1 revolution
Title: Re: Anyone know tach ratios?
Post by: memper on November 04, 2012, 05:08:49 PM
Thanks so much!
Title: Re: Anyone know tach ratios?
Post by: memper on November 04, 2012, 06:44:48 PM
Ha! Too bad they're impossible to find. Seems my options are digital, and I hate digital. What would my read out be with a 2:1? Would 1000 rpm read 500 or something like that? I could live with it being off if I knew exactly how off it would be if in fact I can't find a 1:1 electronic dial.
Title: Re: Anyone know tach ratios?
Post by: motoxmann on November 04, 2012, 10:09:05 PM
if you used a 1:2 tach, it'd read double the actual engine speed. so if the engine is at 7k, the tach would read 14k
why not just get the ducati performance tach? it matches the stock speedo
Title: Re: Anyone know tach ratios?
Post by: Howie on November 04, 2012, 11:20:11 PM
http://www.spatechnique.com/product_pages/page.cfm?cat=3 (http://www.spatechnique.com/product_pages/page.cfm?cat=3)

They have one that will fit in place of your speedometer with a small digital speedometer and odometer in it.  Start measuring or maybe ducpainter can help you.   He has one in his bike.
Title: Re: Anyone know tach ratios?
Post by: memper on November 05, 2012, 05:33:10 AM
Thanks MM. Dont think I will be doing 2:1.
Howie, those are neat but for hundreds of dollars..... :-X

I simply want a small basic tach. Guess I'll have to keep on lookin.

thx yall
*edit: went with a small round digital found on Amazon. Says its good for bikes, 2cyl, 4 cyl, 2 stroke, 4 stroke. I guess we'll see...
Title: Re: Anyone know tach ratios?
Post by: Speeddog on November 05, 2012, 01:04:22 PM
Here's a small tacho:
http://egauges.com/cyc_mult.asp?Type=2_5_8_Street_Tach_Black&Series=Pro-Cycle (http://egauges.com/cyc_mult.asp?Type=2_5_8_Street_Tach_Black&Series=Pro-Cycle)
Title: Re: Anyone know tach ratios?
Post by: memper on November 05, 2012, 04:32:03 PM
Quote from: Speeddog on November 05, 2012, 01:04:22 PM
Here's a small tacho:
http://egauges.com/cyc_mult.asp?Type=2_5_8_Street_Tach_Black&Series=Pro-Cycle (http://egauges.com/cyc_mult.asp?Type=2_5_8_Street_Tach_Black&Series=Pro-Cycle)

Very nice but if I'm gonna spend $200+ I will likely put it toward better riding gear (like new gloves). I just needed something simple, effective and cheap. So I went for the digital universal one. But as they say, you get what you pay for...so likely it will malfunction riiiight after the warranty is up.