4rt RPM idle tach

[dannyb]

Hi, just picked myself up a repsol 260 - what a bike! ?

Can anyone recommend a reliable and easy to use tachometer for setting the idle speed please ? 

Is something like this suitable? https://www.ebay.co.uk/itm/UNI-T-LCD-Digital-Tachometer-Speedometer-Tach-Meter-Measuring-Rang-0-99999-P8T8/312860215918?hash=item48d7ec0a6e:g:s4kAAOSww5Zd20vg

I'm led to believe this needs to be checked regularly as the atmospheric conditions can affect and alter the idle speed... any truth in this? Does the operating temperature of the engine also affect the idle (I.e. hotter engine = higher idle speed) or does the efi self calibrate this?

 

Thanks in advance  

[2stroke4stroke]

You need one that senses the pulses in the HT lead. The one pictured needs sight of a rotating flywheel.  The small ones (matchbox size) from China last about a fortnight. I got one of these but it only lasted a few goes  https://www.machinemart.co.uk/p/draper-automotive-tachometer/   

I do find the speed can vary during an event and it does rise when the fan comes on.

As a by the by, if you find it hard to adapt to the fast tickover you could lower the gearing. I went to 9 teeth on the front but that's a bit cruel to the chain so went up two teeth on the rear instead when replacement time came round and find that a good compromise on my 250 (I'm not one for using the clutch all the time).  When I briefly rode a 260, although the gearing is the same as the standard 250, it felt to run a bit slower as if the gearing was lower - I can't explain that.

 

Edited November 25, 2019 by 2stroke4stroke

[300strokes]

Hi, tickeover needs to be 1800rpm and if its lowered the bike will be a pig to start. The heat and atmospheric pressure will not bother the bike as that's what the ECU does and alters its own mixture to suit.

Try these tachometers they are very good. http://www.trailtechproducts.co.uk/acatalog/Tach_Hour.html

[motovita]

 I use the 20K tach here

https://www.tinytach.com/handheld-tachometers

 I'm sure there will be some outrage expressed here, claiming that it's too expensive.

[dannyb]

Thanks for the help and the info. I found i had one of the cheap tachs already in my toolbox so hooked it up to see what it read. It appeared to be a little high so turned the idle down a quarter turn.

One thing i noted is the readout (digital) fluctuates a little as the bike idles - is this normal? Mine as currently set, reads 1800 but will flick to 1680 maybe once every 1 or 2 seconds?? 

[2stroke4stroke]

18 hours ago, dannyb said:

Thanks for the help and the info. I found i had one of the cheap tachs already in my toolbox so hooked it up to see what it read. It appeared to be a little high so turned the idle down a quarter turn.

One thing i noted is the readout (digital) fluctuates a little as the bike idles - is this normal? Mine as currently set, reads 1800 but will flick to 1680 maybe once every 1 or 2 seconds?? 

I don't think that's unusual.

[cord]

I've got the Tunelab Engine RPM app on my iphone, and compared to the MOT testing hardware is consistantly within 20rpm. Well impressed!!!!!!

Edited December 3, 2019 by cord