Topic: Wideband on a cb750?

[orkid1989]

i was wondering if it is possible to run a wideband o2 sensor on my 71 cb750? i checked the specs of the sensor online and it has a 12v 1.2amp digital gauge. my bike is a 71 cb750k with a 4 to 1 exhaust. it will have (in the mail at the moment) 5ohm dyna coils and the only other modification to the electrical system is that i added led blinkers. i know that i can mount it and everything but my question is will the electrical system have any problems with it?
http://www.aemelectronics.com/wideband-o2-air-fuel-uego-gauge-kit-745

[rklystron]

You should have no problems running 1 wideband O2 sensor. I know a bit about the Bosch 3737 Wideband O2 Sensor. The electrical system can handle the preheat on the sensor. A single channel O2 will draw about 1 amp. I have run 4, O2 sensors and found that in my application I required more power at initial O2 heat cycle start-up. No worries in your case. All the best!

[orkid1989]

You should have no problems running 1 wideband O2 sensor. I know a bit about the Bosch 3737 Wideband O2 Sensor. The electrical system can handle the preheat on the sensor. A single channel O2 will draw about 1 amp. I have run 4, O2 sensors and found that in my application I required more power at initial O2 heat cycle start-up. No worries in your case. All the best!

great. thanks.

[cougar]

Hey orkid; I'm not sure how to say this, LOL. I assume yor going to do this for tuning purposes. If so, unless you place a bung (for your sensor), in each pipe and block 3 off while your tuning 1 cylinder, that you'll be putting it in the collector somewhere. If you place it in the collector you'll only be able to do some what of a rough tune using it there because all 4  of your gasses will be mixed bu that point. So for a proper tune you might want to do what' in the first half of the third line . Hmmm.   ...cougar...

[orkid1989]

Hey orkid; I'm not sure how to say this, LOL. I assume yor going to do this for tuning purposes. If so, unless you place a bung (for your sensor), in each pipe and block 3 off while your tuning 1 cylinder, that you'll be putting it in the collector somewhere. If you place it in the collector you'll only be able to do some what of a rough tune using it there because all 4  of your gasses will be mixed bu that point. So for a proper tune you might want to do what' in the first half of the third line . Hmmm.   ...cougar...

no i am not meaning it for tuning. just to kinda get a rough guess. putting it in the collector will give it a rough guess of the average between all 4 cylinders. also it will help when riding to make sure it isnt running extremely lean or rich. plus it would just be cool to have a wideband on a bike lol

[Don R]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, 4 diameters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

[orkid1989]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, $ diamaters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

ah well mine has the cyclex git kit 2. so do you think my idea will work with installing it in the collector? kinda just looking at getting a balpark guess on tuning. more for show than performance

[MRieck]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, $ diamaters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

ah well mine has the cyclex git kit 2. so do you think my idea will work with installing it in the collector? kinda just looking at getting a balpark guess on tuning. more for show than performance

I have a bung welded in the rear of the collector. i had an earlier A/F system which basically blew monkeys. The wideband would work much better. I will be using after my current build.
 Many, many modern aftermarket and OEM 4/1, 4/2/1 have the bung just rear of the collector section. MotoGP bikes do. I have not seen individual sensors on each exhaust manifold pipe on automobiles though I'm not a car tech.

[MRieck]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, $ diamaters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

And you thought reversion would not be bad?

[orkid1989]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, $ diamaters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

ah well mine has the cyclex git kit 2. so do you think my idea will work with installing it in the collector? kinda just looking at getting a balpark guess on tuning. more for show than performance

I have a bung welded in the rear of the collector. i had an earlier A/F system which basically blew monkeys. The wideband would work much better. I will be using after my current build.
 Many, many modern aftermarket and OEM 4/1, 4/2/1 have the bung just rear of the collector section. MotoGP bikes do. I have not seen individual sensors on each exhaust manifold pipe on automobiles though I'm not a car tech.

well one on each pipe would be much better but im not using it to tune. i have someone who is going to dyno tune it when im done. im kinda just thinking it will give a pretty good ballpark guess on the A/F ratio. also aem has a cool new strap thing on their site where it has the bung on it so all you have to do is drill a hole in the exhaust then install the strap then the o2 sensor
http://www.aemelectronics.com/no-weld-o2-sensor-mount-2-inch-660

[MRieck]

Look at it this way...the dyno A/F meter can only read from 1 source. The 4/1 works in your favor under that condition.

[Sam Green Racing]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, $ diamaters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

ah well mine has the cyclex git kit 2. so do you think my idea will work with installing it in the collector? kinda just looking at getting a balpark guess on tuning. more for show than performance

If it's more for show, why not ask Jay at APE for some go faster stickers that way it will be much cheaper.
I often wonder when people do/fit things just for show (how many times have you heard it on here) do they ever consider how many people will see what they have done and not have a clue what it is.  
If you have to much money, just send it to me.

Sam.

[orkid1989]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, $ diamaters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

ah well mine has the cyclex git kit 2. so do you think my idea will work with installing it in the collector? kinda just looking at getting a balpark guess on tuning. more for show than performance

If it's more for show, why not ask Jay at APE for some go faster stickers that way it will be much cheaper.
I often wonder when people do/fit things just for show (how many times have you heard it on here) do they ever consider how many people will see what they have done and not have a clue what it is.  
If you have to much money, just send it to me.

Sam.

haha no im more wanting it for me. mostlikley nobody other than me will notice it anyway. not a bad idea with the stickers though lol

[Sam Green Racing]

Ha Ha, only messing with you Ork, but if you have any spare money.

 Sam.

[lordmoonpie]

I ran lambda sensors on my VTR racers and they are incredibly useful to know when there is an engine problem. Most of the time the indicator just flicks around as the mixture alters the gases at different throttle opening s but a couple of times I hit big engine problems and saw it actually occur on the sensor as it swung way out of sensible operating range. Clutch in, park it and you end up with minimal damage as a result....great things if you can afford them and not just bling! :-)

[MidnightLamp]

http://14point7.com/

Cheap enough to run four! Look at the OEM versions!

[orkid1989]

just ordered my wideband setup.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=200653545522&ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

i was wondering what would be the best to tune it too? i know normally it is 14.7 but wasnt sure if it is any different with an air cooled engine

[orkid1989]

i was searching all over the internet and someone mentioned 13 to 1 for air cooled. does that sound right?

[Don R]

I know it's apples and oranges but on my dragster the O2 sensor is way up in the primary tube, $ diamaters from the port, and at lower rpm's it spikes like crazy due to reversion. I would not have believed that fresh air would be sucked back that far. It does. That said, my engine has a gynormous cam .800 plus lift. and tons of overlap.

And you thought reversion would not be bad?

I expected reversion but not that far up the tube.  My point is at low flow the o2 near the end of the pipe may read  lean. At higher rpm the flow should be steady enough to keep reversion at a minimim and get a better reading.

[BrianAdair]

I have been researching this for about the past 2 weeks considering doing it also, and now I stumble upon this thread tonight. I would be doing it for more tuning purposes than for looks, I don't even know if I would leave it mounted permanently. I was thinking the same as some one else said earlier, if it was in the collector it would be a rough average, you still have to guess at where you are on each individual cylinder, but I feel it would help find a ballpark figure. I was considering tapping all four head pipes but I wouldn't want to see the plugs on my header, I was first looking into the narrow band but it seems it is more of just a jumping light show, from rich to lean and never consistent, I think they read from 0 to 1v   and .5v is suppose the be 14.7:1 AFR. So I started looking into the wide-band i think they are 0 -5v , I also was researching how to build the controller instead of buying one, but later found that it's almost just as much as just buying the kit. I was wanting to just use in the shop to test through the throttle positions, with the rear wheel on rollers and the front bound down instead of running down the road, I guess you mite say a home made dyno in a way. I have set my carbs the shade tree way first with a bench sync, then gauges, and running down the road and seeing if it surged, check plugs, shaved the slides down .010 to close the air cutaways, (POD air filters) yes they SUCK. 849cc 10:1cr, ported head, stainless manly valves, hd springs, stock cam, '73 carbs 120mains, 40 idles, air screws 3/4 turn out needles in the middle clip setting. No surging, the only thing is at WOT after a few seconds I get denotation, if I raise the needle one setting then I'm too rich, so I'm thinking of trying 125mains, at cruising speed of 70mph seems good, although I would really like to know where I'm at in the AFR, So that's my reason for wanting to do this, I would much rather run at 12:1 or 13:1 rather than be at 18:1.
An advantage I could see with it being mounted permanently is when the weather changes, you can monitor if your running lean or rich and make the adjustments for that time of year.

[orkid1989]

I have been researching this for about the past 2 weeks considering doing it also, and now I stumble upon this thread tonight. I would be doing it for more tuning purposes than for looks, I don't even know if I would leave it mounted permanently. I was thinking the same as some one else said earlier, if it was in the collector it would be a rough average, you still have to guess at where you are on each individual cylinder, but I feel it would help find a ballpark figure. I was considering tapping all four head pipes but I wouldn't want to see the plugs on my header, I was first looking into the narrow band but it seems it is more of just a jumping light show, from rich to lean and never consistent, I think they read from 0 to 1v   and .5v is suppose the be 14.7:1 AFR. So I started looking into the wide-band i think they are 0 -5v , I also was researching how to build the controller instead of buying one, but later found that it's almost just as much as just buying the kit. I was wanting to just use in the shop to test through the throttle positions, with the rear wheel on rollers and the front bound down instead of running down the road, I guess you mite say a home made dyno in a way. I have set my carbs the shade tree way first with a bench sync, then gauges, and running down the road and seeing if it surged, check plugs, shaved the slides down .010 to close the air cutaways, (POD air filters) yes they SUCK. 849cc 10:1cr, ported head, stainless manly valves, hd springs, stock cam, '73 carbs 120mains, 40 idles, air screws 3/4 turn out needles in the middle clip setting. No surging, the only thing is at WOT after a few seconds I get denotation, if I raise the needle one setting then I'm too rich, so I'm thinking of trying 125mains, at cruising speed of 70mph seems good, although I would really like to know where I'm at in the AFR, So that's my reason for wanting to do this, I would much rather run at 12:1 or 13:1 rather than be at 18:1.
An advantage I could see with it being mounted permanently is when the weather changes, you can monitor if your running lean or rich and make the adjustments for that time of year.

awesome and thanks for the chart and all of the info. and either way it can be removed and plugged but i think it will look cool and serve its purpose being mounted to the bike. and from what ive seen it is always better to be a little more rich than lean because of the motor. just curious but why did you decide to use the stock cam with all the other performance stuff?

[orkid1989]

[BrianAdair]

I have been researching this for about the past 2 weeks considering doing it also, and now I stumble upon this thread tonight. I would be doing it for more tuning purposes than for looks, I don't even know if I would leave it mounted permanently. I was thinking the same as some one else said earlier, if it was in the collector it would be a rough average, you still have to guess at where you are on each individual cylinder, but I feel it would help find a ballpark figure. I was considering tapping all four head pipes but I wouldn't want to see the plugs on my header, I was first looking into the narrow band but it seems it is more of just a jumping light show, from rich to lean and never consistent, I think they read from 0 to 1v   and .5v is suppose the be 14.7:1 AFR. So I started looking into the wide-band i think they are 0 -5v , I also was researching how to build the controller instead of buying one, but later found that it's almost just as much as just buying the kit. I was wanting to just use in the shop to test through the throttle positions, with the rear wheel on rollers and the front bound down instead of running down the road, I guess you mite say a home made dyno in a way. I have set my carbs the shade tree way first with a bench sync, then gauges, and running down the road and seeing if it surged, check plugs, shaved the slides down .010 to close the air cutaways, (POD air filters) yes they SUCK. 849cc 10:1cr, ported head, stainless manly valves, hd springs, stock cam, '73 carbs 120mains, 40 idles, air screws 3/4 turn out needles in the middle clip setting. No surging, the only thing is at WOT after a few seconds I get denotation, if I raise the needle one setting then I'm too rich, so I'm thinking of trying 125mains, at cruising speed of 70mph seems good, although I would really like to know where I'm at in the AFR, So that's my reason for wanting to do this, I would much rather run at 12:1 or 13:1 rather than be at 18:1.
An advantage I could see with it being mounted permanently is when the weather changes, you can monitor if your running lean or rich and make the adjustments for that time of year.

awesome and thanks for the chart and all of the info. and either way it can be removed and plugged but i think it will look cool and serve its purpose being mounted to the bike. and from what ive seen it is always better to be a little more rich than lean because of the motor. just curious but why did you decide to use the stock cam with all the other performance stuff?

Well, I have a cam that I tried running, but never could get it to idle under 4k, so I just threw the stock back in for the time being, until I can afford a milder cam. The one i have I have no specs on and can't seem to find out what it is other than huge, and the stock carbs I don't think are big enough for that cam I was running way lean. It was just to much bs to deal with and i wanted to ride it...lol
i may try it again since winter is about to come on and get some of the Mikuni VM34 carbs Cycle x has. that is if I find a money tree..
Yes, rich runs cooler and safer, replacing fouled plugs is cheaper than melting pistons or seizing rings.

[orkid1989]

I have been researching this for about the past 2 weeks considering doing it also, and now I stumble upon this thread tonight. I would be doing it for more tuning purposes than for looks, I don't even know if I would leave it mounted permanently. I was thinking the same as some one else said earlier, if it was in the collector it would be a rough average, you still have to guess at where you are on each individual cylinder, but I feel it would help find a ballpark figure. I was considering tapping all four head pipes but I wouldn't want to see the plugs on my header, I was first looking into the narrow band but it seems it is more of just a jumping light show, from rich to lean and never consistent, I think they read from 0 to 1v   and .5v is suppose the be 14.7:1 AFR. So I started looking into the wide-band i think they are 0 -5v , I also was researching how to build the controller instead of buying one, but later found that it's almost just as much as just buying the kit. I was wanting to just use in the shop to test through the throttle positions, with the rear wheel on rollers and the front bound down instead of running down the road, I guess you mite say a home made dyno in a way. I have set my carbs the shade tree way first with a bench sync, then gauges, and running down the road and seeing if it surged, check plugs, shaved the slides down .010 to close the air cutaways, (POD air filters) yes they SUCK. 849cc 10:1cr, ported head, stainless manly valves, hd springs, stock cam, '73 carbs 120mains, 40 idles, air screws 3/4 turn out needles in the middle clip setting. No surging, the only thing is at WOT after a few seconds I get denotation, if I raise the needle one setting then I'm too rich, so I'm thinking of trying 125mains, at cruising speed of 70mph seems good, although I would really like to know where I'm at in the AFR, So that's my reason for wanting to do this, I would much rather run at 12:1 or 13:1 rather than be at 18:1.
An advantage I could see with it being mounted permanently is when the weather changes, you can monitor if your running lean or rich and make the adjustments for that time of year.

awesome and thanks for the chart and all of the info. and either way it can be removed and plugged but i think it will look cool and serve its purpose being mounted to the bike. and from what ive seen it is always better to be a little more rich than lean because of the motor. just curious but why did you decide to use the stock cam with all the other performance stuff?

Well, I have a cam that I tried running, but never could get it to idle under 4k, so I just threw the stock back in for the time being, until I can afford a milder cam. The one i have I have no specs on and can't seem to find out what it is other than huge, and the stock carbs I don't think are big enough for that cam I was running way lean. It was just to much bs to deal with and i wanted to ride it...lol
i may try it again since winter is about to come on and get.some of the Mikuni VM34 carbs Cycle x has. that is if I find a money tree..
Yes, rich runs cooler and safer, replacing fouled plugs is cheaper than melting pistons or seizing rings.

Wow can't idle under 4k that sounds like a massive cam. I just got the cam that cycle x supplied and it idles at about 1200rpm. I assume it is running lean with 40 pilot jets and 130the mains with the needle raised a clip. I was having bad performance due to the crappy pod filters the previous owner installed so I ripped them off while riding down the roan then the performance for way better (two of the filters were clogged)

[23tbucket]

I've got a supercharged, fuel injected CB750 and a turbocharged, fuel injected CB750. An O2 sensor is priceless. This is a little info I've gathered over the years that I try to tune for. Using an O2 sensor on one of these old air cooled Honda's and getting the ratio correct is a big grey area yet for me. Others may have better info.....I'm open to any and all suggestions.

10.5 - 11.4    Rich A/F

11.6 - 12.3    Ideal A/F

12.5 - 14.7    Lean A/F

14.0 - 18.0    Very lean A/F

These little engines seem to idle smoothest on the rich side (mine does anyway!)...say 10.0 - 11.5

For good all round power 12.8 - 13.2

12.5 is a good safe zone

11.4 - 11.8 if boosted

Never boost above 12.5