A forum for owners of Yamaha TTR250 trail and enduro bikes!

Members Login
Username 
 
Password 
    Remember Me  
Post Info TOPIC: O2 Oxygen sensor as a means to measure fuel:air ratio DIY


Veteran Member

Status: Offline
Posts: 30
Date:
O2 Oxygen sensor as a means to measure fuel:air ratio DIY
Permalink  
 


Hi all,

I am home with the flu no, so as usual to pass the time,laptop on my belly I started to google and gather information  on my latest and hopefully helpful idea.

we all know that a fuel/air metering device is expensive, yet it can give us much needed information on the mixture our motor is running on..lean rich or optimum. From then on we can re jet and fine tune our motor and retest it.

further reading has given me an idea to purchase a car o2 sensor and hook it up to a voltmeter. The range should be set in the low volts range 0 to 1.0 volts . The optimum voltage reading has to be 450 mv (0.45 Volts) equivalent to 14.7 : 1 air : fuel ratio

O2 sensors must reach 315 Celsius to give a correct reading so a heat resistant long wire hose is needed to insert the "probe" further into the muffler.

Of course one can purchase an Air Fuel meter Gauge  but to keep the costs low a simple Voltmeter would do.

Further reading :

http://my.prostreetonline.com/2013/08/28/471/

 

http://www.youtube.com/watch?v=YL6xkOZxHZ0

 

http://www.youtube.com/watch?v=XQYDwIWS6Ho

 

I will be purchasing a cheap one from ebay it will take a month until I receive it and hook it up

if anybody tried it or will try it before me , let me know smile

Cheers :)

   

 

 

 

 

 

 

 



__________________


Super Guru

Status: Offline
Posts: 1385
Date:
Permalink  
 

I started to look into this myself not long ago, when I first fitted my 325 engine and wanted to know how it was running. Afraid I gave up in the end, but several people I spoke to suggested using a 4 wire lambda sensor - they heat themselves and so don't need to be placed in the header. Also means you can minimise the obstruction to flow. Alternatively, buy another header pipe and weld in a sensor boss close to the cyl head end. You could then either replace the original when you're happy with the readings, simply plug the boss in case you want to do more testing, or leave the sensor in and start developing a fuel injection system for the ttr... Sorry, getting carried away. I'll get my coat!
Ride safe, (especially when trying to read that voltmeter at full whack in 6th!)
Simon.

__________________


Super Guru

Status: Offline
Posts: 8565
Date:
Permalink  
 

I have borrowed one of these K&N air/fuel ratio monitors to try. Had it on my desk for about 2 years waiting to try it disbelief

Instructions here

Has anyone got any experience of using such a device on a dirtbike?

I have a spare header pipe and it has been suggested that I weld the boss for the sensor as close to the head as possible to get the heat.

Looking forward to watching this thread develop biggrin

Regarding fuel injection, I saw on a Car S.O.S. programme that they fitted a fuel injector on a Herald 13/60 motor which improved it no end. As usual with those programmes it was very short on any detail cry

Brian

 



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Super Guru

Status: Offline
Posts: 1156
Date:
Permalink  
 

I have a A/F gauge for the XT660...
scew the sencer into the lambarda
sencer plug in the header pipe..
But the XTR is injected & i have a mod
that connects to the air temp sencer in the air
box..by turning a nob I can tell lies to the
ECU about how hot the air temp is.. then the ECU
will richen or lean off the A/F ratio.
So with that & the A/F gauge I can set the A/F ratio
to anything I wish with in the ECUs pre-set perammiters...
which seem to be 12.5/1 to 15.5/1..can't get it above
or below that.. or maybe the mod dosn't tell big enough lies...

So theres no reason why you can't do it with a carb...


__________________

 

.....................................................................................................

 http://www.kiwibiker.co.nz

Bikes... 06 TTR250 / 09 XT660R / 1977 Montesa Cota 348 MRR / 1979 Montesa H6 125 Enduro...

E-mail  xtpete1@gmail.com



Veteran Member

Status: Offline
Posts: 30
Date:
Permalink  
 

Simon, thanks for your feedback
Brian, you have the tool, start drilling and tapping hehe, you ll be a much popular guy than you r already are :)


So my improved idea would be the following.

I already have a digital tach fitted on the handle bar so the idea would be to temporarily attach the Voltmeter beside it, borrow a go pro and take a video of both readings.

then analyse both data safely back home, rejet and re test.
Still waiting eagerly for the sensor :) and Btw I purchased the 4 wire one cause as you said, it has a heater to get it working sooner.

Cheers I will keep you updated later on mid December , I hope.

Henry





__________________


Veteran Member

Status: Offline
Posts: 53
Date:
Permalink  
 

I use a wideband for mapping cars . .

__________________
Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard