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Discussion Starter #1
BEWARE = LX579 Sensors are not created Equal

I have been struggling with the simple sensor upgrade this weekend.

In talking to to one forum member for guidance, I was informed that some of the new sensors did not fit. I was told to use the SMC sensor In looking at my stock that I had allready purchased, I found that mine were SMP (Standard Motor Products) I assumed that the info I was told had the wrong acronym as I could not find any SMC sesnsors.

In proceeded but later found out that the ones that I had did not work. Actually I had purchased 3 sensors from the same source. The odd thing was that one of them was OK and two of them did not work. Below is a picture showing them. The one on the left does not work as many of the pysical dimensions, while close to the original, are larger. These are critical enough that it does not fit in the cutout area in the sensor plate. I have been trying to use a dremel tool to cut it down but this is going very slowly. As a result, I am on the hunt to find a source for these sensors that provides the one that fit our applications.



If you look closely, the one that worked is marked JAPAN, and has a part number stamped on it. I cannot read the part number. I am not sure if meaningful, but both the sensors that did not worrk had the green colored core area. The picture below shows the markings on the sensor that would have worked.

 

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I don't remember how old it was, but I posted replacement sensor unit, swapping from Suzuki.
Some Suzuki are using exactly the same speed sensor distributed by ND, Nippon Denso.
 

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Discussion Starter #3
I don't remember how old it was, but I posted replacement sensor unit, swapping from Suzuki.
Some Suzuki are using exactly the same speed sensor distributed by ND, Nippon Denso.

OK I could be confused or could have missed something but I thought the Suzuki information was for the pressure sensors that replace the P one sensor. for the crankshaft position sensor's I remember people talking about Toyota replacements (lx579). PiM has also given me information about the sensor in a gold wing Aspincade in the 19 75/76 timeframe. I have confirm that the Gold wing sensors are identical I just need to find some of those however I would rather than buying something 34 years old to replace something 34 years old I would like to buy a new replacement if that's possible . From the information I have a red people are finding new sensors at work it's just that I seem to have stumbled across it combination of something at work and some that do not work or require a lot of grinding and some adjustment to make them fit . If someone knows of a source to buy some exact drop in replacements that's information I would like to find. They do exist because I bought three from the same person to that don't fit in one that does .

Based on your information when I get home tonight I will try searching for Suzuki or Nippon Denso or by you as author, that mayyield better search results .

Thanks for the feedback
 

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Some Suzuki are using exactly the same speed sensor distributed by ND, Nippon Denso.
Noir is right, these can be found on the GSX, GSXR models



But if I remember correctly , our member DutchTurbo tried to use them, the only problem was that the wires got brittle and stiff because of the heat inside the engine
 

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I don't understand these coils with green will not work when the resistance is between 100 and 250 Ohms. If the green ones don't match that resistance they sure will not work.
Nobody ever talks about the resistance but it is wise to measure them before you mount them. My LX579 measure 190 Ohm so they are good for the job.
And also very important: wrong polarity will not work either.

I have bought a Suzuki GSXR sensor including the wiring but this was not a success. The wires were hardened and brittle cause of the heat from the engine and broke when you tried to bend them.
 

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Discussion Starter #6
I don't understand these coils with green will not work when the resistance is between 100 and 250 Ohms. If the green ones don't match that resistance they sure will not work.
Nobody ever talks about the resistance but it is wise to measure them before you mount them. My LX579 measure 190 Ohm so they are good for the job.
And also very important: wrong polarity will not work either.

I have bought a Suzuki GSXR sensor including the wiring but this was not a success. The wires were hardened and brittle cause of the heat from the engine and broke when you tried to bend them.
I believe they will work, electrically. All I am saying is that the potted housing is larger than the origninal such that it will not fit in the mounting plate without some physical grinding down of the case or grinding the mounting plate larger.

I think sensors are more readily available than the mounting bracket, so I am a little reluctant to grind on that. I am using a dremel tool to grind away at the plastic housing in areas such that it will fit. This is turning out to be a pain in the rear.

Would be much better to find a new senstr that just fits. Like I said, I ordered three from one source and got two knockoffs and one original, so it seems like there are new ones outthere with the profile that will fit. I am just trying to find a method of being able to order so you know you are going to get the correct onel.
 

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OK I could be confused or could have missed something but I thought the Suzuki information was for the pressure sensors that replace the P one sensor. for the crankshaft position sensor's I remember people talking about Toyota replacements (lx579). PiM has also given me information about the sensor in a gold wing Aspincade in the 19 75/76 timeframe. I have confirm that the Gold wing sensors are identical I just need to find some of those however I would rather than buying something 34 years old to replace something 34 years old I would like to buy a new replacement if that's possible . From the information I have a red people are finding new sensors at work it's just that I seem to have stumbled across it combination of something at work and some that do not work or require a lot of grinding and some adjustment to make them fit . If someone knows of a source to buy some exact drop in replacements that's information I would like to find. They do exist because I bought three from the same person to that don't fit in one that does .

Based on your information when I get home tonight I will try searching for Suzuki or Nippon Denso or by you as author, that mayyield better search results .

Thanks for the feedback

Let me clear the one thing. My reply was posted since I thought you are working on a "Engine Speedo Sensor." If I were mistaken, please just ignore. lol

Sensors Suzuki using are totally identical as the CX-T uses, but you can't swap the assembly unit. You need to use CX-T's base plate and adapter to reconstruct exact the same height as CX-T has.

Best regards,
 

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I've found that some other brands/ manufacturers don't have the same shape/design to the body. That is why it is important to use Standard Motor Company replacements. SMP LX579 fit perfect...

PK
 

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Discussion Starter #9
I've found that some other brands/ manufacturers don't have the same shape/design to the body. That is why it is important to use Standard Motor Company replacements. SMP LX579 fit perfect...

PK
hey Pete, Sort of hoped you would drop in as I talked with you about this. One thing I was confused at is I could not find a sensor from Standard Motor Company. I did find that I had sensors from SMP or Standard Motor Product. Is this what you meant? In any event, I ordered 3 sensors from one source on the internet all described as SMP. However when I got them, Two were one kind and the third was different. The two similar ones were like you stated and did not have the correct pyysical fit. The third did, so like you said, there are new sensors out there that do fit exactly. I noticed the one that fit was marked "JAPAN? and had a part number on it that I could not read. Maybe if I get a magnifying glass I can read it, I will have to take a look.
 

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Discussion Starter #10
Tonight I did some work on thise. Here are some resistance Readings.

a) The original BLUE WIRE SENSOR measured 163.1 ohms
b) The original YELLOW WIRE SENSOR measured 162.6 ohm
c) One of the new GREEN FACED sensors that do not fit measured 176.4 ohms (I had this one in the BLUE WIRE POSITION NOTE that measurement includes the wire length and connector terminals)
d)The second new GREEN FACED sensors that do not fit measured 175.8 ohms (I had this one in the YELLOW WIRE POSITION NOTE that measurement includes the wire length and connector terminals)
e) finally, I had a new sensor that fits exactly, this is the one that is marked with JAPAN. It measured 174.6 ohms.

I personally am not sure what the spec says, but from the information I have read from everyone else, I beleive all of the above sensors to be IN SPEC and usable. I thought I read someone say less than 200 ohms.
 

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Discussion Starter #11 (Edited)
Fitment problems of new sensors. Below is a picture of a old sensor (GOOD ONE) in the mounting plate. The new sensors that do not fit have two areas where fitment is an issue as shown in the diagream below



Below is a new sensor in the bracket. As you can see, there is no chamfer. The edge is square so it does not fit.



Looking at the front of the new sensor, you can see that it is wider and does not fit in between the spaces in the bracket.


so how much wider is it? The pictures below show the answer. The new sensor is 16.69mm while the old sensor is 14.76mm



There is also a difference in height. The new sensor is 20.06mm while the old sensor is 19.63mm, althought I think this is less critical



In order to address this issue, I found a different attachment to my dremel tool, one that was more coarse. This easily removed excess material. I was using way to fine of a grit before.


With the above, I was able to put a chamfer on the edge and then remove material on the other edges so it fits between the brackets. I think this is going to work and I will have to report back when I get everything cleaned up.

I purchased thes sensors on line (EBAY) for under $14
 

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It seems the green ones aren't LX579. There are many more in this shape but have different numbers and resistance. Also slightly different shapes.
I think your supplier send you two wrong ones. Should tell him that and replaced them for the right ones.
 

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OK I could be confused or could have missed something but I thought the Suzuki information was for the pressure sensors that replace the P one sensor. for the crankshaft position sensor's I remember people talking about Toyota replacements (lx579). PiM has also given me information about the sensor in a gold wing Aspincade in the 19 75/76 timeframe. I have confirm that the Gold wing sensors are identical I just need to find some of those however I would rather than buying something 34 years old to replace something 34 years old I would like to buy a new replacement if that's possible . From the information I have a red people are finding new sensors at work it's just that I seem to have stumbled across it combination of something at work and some that do not work or require a lot of grinding and some adjustment to make them fit . If someone knows of a source to buy some exact drop in replacements that's information I would like to find. They do exist because I bought three from the same person to that don't fit in one that does .

Based on your information when I get home tonight I will try searching for Suzuki or Nippon Denso or by you as author, that mayyield better search results .

Thanks for the feedback
I joined this forum on the recommendation of a friend who has a CX650T and an '85 GL1200 Limited Edition. I find that this forum has a lot of the same concerns as I do regarding the fuel injection system and keeping it going. I'm also a bit late to this thread; however, I thought I'd add some information.

There are a lot of similarities in parts between bike model and year other than the fuel injection control system between these bikes.

The PB (pressure barometric) sensors on the '85 LTD are no longer available, same as for the CX650T FI; however, I gleaned from another thread here of a potential fix with a Suzuki MAP sensor. I have ordered two of these to install on my '85 LTD.

The pulse generator sensor(s) for the CX650T is an assembly that has the same part number (first five in the P/N) as the camshaft angle sensors (GR/GL) for the '85 LTD that are on the rear of the right cylinder head. This camshaft sensor measures the specific angular position of the crankshaft. This ECU then determines the fuel injection and ignition timing for both cylinder banks.

There is one additional sensor on the '85 LTD that is located in the front of the engine called the Ns - crankshaft angle sensor. This sensor detects variations in the crankshaft speed and the signal is processed by the ECU to determine fuel injection and ignition timing. I do not believe there is one on the CX650T or the 500 variant.

From what I have read here the recommended replacement for the GR/GL sensors on my '85 LTD would be the LX579. The OEM sensors for the '85 LTD are no longer available. I will be doing more research on these and other possible solutions (if available) as well. I will also check the GR/GL sensor size and compare the readings with the information here.

The info on the '85 LTD is also the same for the '86 SE-i (special edition - injected that was only sold in the US).

Cheers
 

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There is one additional sensor on the '85 LTD that is located in the front of the engine called the Ns - crankshaft angle sensor. This sensor detects variations in the crankshaft speed and the signal is processed by the ECU to determine fuel injection and ignition timing. I do not believe there is one on the CX650T or the 500 variant.

Yes we have such a Ns sensor on both turbo's in the back of the engine. The 500T has two and the 650T one.
 

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There is one additional sensor on the '85 LTD that is located in the front of the engine called the Ns - crankshaft angle sensor. This sensor detects variations in the crankshaft speed and the signal is processed by the ECU to determine fuel injection and ignition timing. I do not believe there is one on the CX650T or the 500 variant.

Yes we have such a Ns sensor on both turbo's in the back of the engine. The 500T has two and the 650T one.
Will look for it. Thanks
 

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There is one additional sensor on the '85 LTD that is located in the front of the engine called the Ns - crankshaft angle sensor. This sensor detects variations in the crankshaft speed and the signal is processed by the ECU to determine fuel injection and ignition timing. I do not believe there is one on the CX650T or the 500 variant.

Yes we have such a Ns sensor on both turbo's in the back of the engine. The 500T has two and the 650T one.
Have browsed the parts fiche and have yet to find it. Can be a quest sometimes to find certain parts. I did browse other model years for a similar Ns sensor for my '85 and found that the 2005-2006 CBR 600 30300-MBW-J21 may be a fit for a single installation. The P/N first 5 numbers are the same so it should be a good replacement.

In looking for the Ns sensor found that the TPS for the CX650T is the same as for the '85 LTD. There is a work around for this that uses an aftermarket auto style TPS, have the PDF docs regarding this.

Cheers
 

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found that the 2005-2006 CBR 600 30300-MBW-J21 may be a fit for a single installation. The P/N first 5 numbers are the same so it should be a good replacement.
The first 5 digits of a CBR600 (2001) and a CX500 Turbo (1982) Piston are also the same but I would not think it is a good replacement part ;)
The Honda 5 first digit is simply a code for which kind of part.


This camshaft sensor measures the specific angular position of the crankshaft. This ECU then determines the fuel injection and ignition timing for both cylinder banks.
The Camshaft sensor is only used for the fuel injection and not for ignition , this because the camshaft doesn't rotate accurately enough for ignition timing.

There is one additional sensor on the '85 LTD that is located in the front of the engine called the Ns - crankshaft angle sensor. This sensor detects variations in the crankshaft speed and the signal is processed by the ECU to determine fuel injection and ignition timing.
The crankshaft angle sensor is used for ignition only. The CX500 Turbo has two sensors this because the ignition unit is analog and cannot calculate the timing only the delay. On the CX650 Turbo the ECU computer does the calculations and therefore only needs one, but to make accurate calculations the number of pulse needs to be higher. This can be seen on the flywheel which has more poles to trigger the sensor.

The Honda GL1200L maintenance manual ( Page 10-3) is wrong in this aspect.

So the CX500 Turbo will keep running if one of the two camshaft sensors are broken. It will not run with a faulty crankshaft sensor.

The CX650 Turbo will keep running if one of the two camshaft sensors are broken. It will run with a faulty crankshaft sensor if both camshaft sensors are good.
 

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The Camshaft sensor is only used for the fuel injection and not for ignition , this because the camshaft doesn't rotate accurately enough for ignition timing.

The crankshaft angle sensor is used for ignition only. The CX500 Turbo has two sensors this because the ignition unit is analog and cannot calculate the timing only the delay. On the CX650 Turbo the ECU computer does the calculations and therefore only needs one, but to make accurate calculations the number of pulse needs to be higher. This can be seen on the flywheel which has more poles to trigger the sensor.

The Honda GL1200L maintenance manual ( Page 10-3) is wrong in this aspect.

So the CX500 Turbo will keep running if one of the two camshaft sensors are broken. It will not run with a faulty crankshaft sensor.

The CX650 Turbo will keep running if one of the two camshaft sensors are broken. It will run with a faulty crankshaft sensor if both camshaft sensors are good.
Thanks for the info, always good to get a second opinion. Thought it strange that Honda would use two inputs for the same requirements. Still looking for information and parts that will keep my '85 on the road - never ending quest.

Cheers
 

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Pim - found this same info over on the Steve Saunders Forum - a lot of threads/posts to go through to find various information. The 1200 LTD/SE-i will operate with one GR sensor apparently (hope to never find out), but if both go south bike will not start/operate. If the Ns goes south, bike is dead as well. Will be keeping this in mind for next time. Always learning.

Cheers
 
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