Tach for Honda CM450E

I miss not having a tach on a bike, is there an aftermarket company
that makes a tach that would fit on my '84 cm450e? thanks.

 

Loads of companies sell electronic aftermarket tachometers. Just google.
None of them will be a perfect cosmetic match for your speedometer,
though.

 

Don't want to start a war here. But, how useful is a tachometer to the
average rider. Notice I said average. Yeah, it's a nice instrument to look
at, but, never have I made a shift decision base on a tachometer reading.
Same for all my cars with tachs. Especially my vehicles with automatic
transmissions.
Other than race participants, does anybody look at the tach for any useful
purpose?

Just wondering!

Ivan Vegvary

 

On some bikes, it's pretty near essential. On others, it isn't.

See above. On my little 250, I don't miss it and don't need it. On my
Honda 400 Four, I sure do.

 

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Could you please explain. Is your Honda 400 so quiet that the shift points
are not obvious.

Thanks,

Ivan Vegvary

 

whoops my bad. it should have been worded "i miss having a tach".
sorry.

 

i find a tach useful for troubleshooting carb issues.

 

No. It has a very peaky engine, which starts producing power around
6500rpm. Below that it's rather flat. It's also rather revvy and will
cheerfully (in the lower gears) spin into the red zone.

Now, in order to make progress, as it were, I really need to change up
around 7500rpm in order not to have the revs fall out of the power band.
When making fast progress, I change up a lot higher, and as it is a 30
year-old classic, I really don't like taking it into the red zone - and
preferably not within 1000 rpm of it.

The red zone starts at 10,000 rpm. My aged ears cannot tell the
difference between 9,000 and 10,000 rpm on a little four, and I doubt
yours can either.

Clear?

 

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Yes, clear. Thank you!!

Ivan Vegvary

 

I had not considered most all of the things you mentioned above. My main
experience has been on my 1964 BMW R69S. I've never had it above 80 mph
and, usually, I'm in 4th gear by the time I get to 30 mph. Yes, I can also
reach 30 in 1st gear but have never needed the acceleration. I obviously
ride like a wimp. Anyway, you have given me some good points to think
about, and I guess there are many riders who are much more demanding of
their machines.

Thanks for your ideas,

Ivan Vegvary

 

Ooh! Always wanted to ride one of those.

 

You can hook almost any electronic tach to a coil primary
negative and get some kind of reasonable results.

My twin makes one spark per revolution. For tuning, I
usually use an ancient Sears engine analyzer set on
"four cylinder, narrow band". On this setting, it reads half
the real RPM speed, which still makes it way more
accurate in narrow band mode than a handlebar tach
would be. This unit cost all of $15 on eBay and hooks
into a permanant connection I wired for it off the
spark coil.

For normal riding, I run a Drag Specialties knockoff
made for HD "dual fire" ignitions. Just figure out how
many sparks per revolution or revolutions per spark
and you can match up a tach to the engine. They
generally are driven by a pulsed ground from the coil
negative.