H.E.S. Woes, 96 RT1100

[Woodchips]

Last month I set about doing a MAJOR maintenance on my second RT. It included a new clutch, all fluids, brake flush, new pads, and fork seals. As part of the inspection process I removed the H.E.S. unit to check the wiring and connector.

All was in order so it was reinstalled and that was where my troubles started, It would not start. I pulled the alternator pulley off and found the problem.

While reinstalling the rotor in the alternator pulley, it slipped out of the recess in the pulley and when I tried to restart the motor the rotor was out of alignment and with each rotation of the crankshaft the rotor hit the sensors enough to produce some small metal filings 

I then sent the unit off to Cata Dan for a rebuild. I got the unit back and reinstalled it using the aligning  mark I made before removing it. It took some cranking, but it did start, but only the LEFT side is working. I do have a good spark and when the injector was removed, there was fuel on the Right side.

I have sent a inquire to Cata Dan to clarify if the sensors were replaced or just the wiring replaced but have not heard back yet.

Any suggestions as to what else I can check would be welcome (other then ….you should have…….)

 

Ron

[dirtrider]

1 minute ago, Woodchips said:

Last month I set about doing a MAJOR maintenance on my second RT. It included a new clutch, all fluids, brake flush, new pads, and fork seals. As part of the inspection process I removed the H.E.S. unit to check the wiring and connector.

All was in order so it was reinstalled and that was where my troubles started, It would not start. I pulled the alternator pulley off and found the problem.

While reinstalling the rotor in the alternator pulley, it slipped out of the recess in the pulley and when I tried to restart the motor the rotor was out of alignment and with each rotation of the crankshaft the rotor hit the sensors enough to produce some small metal filings 

I then sent the unit off to Cata Dan for a rebuild. I got the unit back and reinstalled it using the aligning  mark I made before removing it. It took some cranking, but it did start, but only the LEFT side is working. I do have a good spark and when the injector was removed, there was fuel on the Right side.

I have sent a inquire to Cata Dan to clarify if the sensors were replaced or just the wiring replaced but have not heard back yet.

Any suggestions as to what else I can check would be welcome (other then ….you should have…….)

 

Ron

 

Evening Ron

 

Look at your right hand throttle cable right where it enters the adjuster on the throttle body.

 

Problem like you are seeing is usually the cable sitting on TOP of the adjuster rather than down inside the adjuster seat  where it belongs.

[Jim Moore]

If it makes you feel any better I did the same thing. Superglue the cup to the pulley next time. And yeah, check the right lower cable.

[Woodchips]

Thanks Jim

DR suggested the black Locktite CA glue, and it was applied wen the repaired HES was installed. BTW, it works great on a loose helmet trim.

I’m off on a short trip on the other RT tomorrow so will check on the cable when I get back. Something that simple doesn’t usually happen in my garage. 

 

[Woodchips]

Did a quick check of the cable position, it’s in the slot and the cable is riding in the groove. 😖 Off for a mind clearing ride to Banff, maybe it will fix itself while I’m away. 🤪 

[dirtrider]

51 minutes ago, Woodchips said:

Did a quick check of the cable position, it’s in the slot and the cable is riding in the groove. 😖 Off for a mind clearing ride to Banff, maybe it will fix itself while I’m away. 🤪 

 

Afternoon Ron

 

Seeing as you have a 96 1100 bike those bikes have a single throttle cable (no upper/lower cables).

 

Not only could that R/H cable be out of position  on the R/H TB (apparently it isn't)  but there is a very slight chance it could be out of position on the L/H side where the single cable wraps around the L/H side cam then exits over to the R/H TB   (cable outer housing could be  sitting on top of it's seat rather than down in it)-- This doesn't happen often but it can happen.

 

As a quick check make sure that both side TB's are opening (lifting off the idle stop screws at exactly the same time) & hitting the wide open throttle stops at exactly the same time.

 

If the R/H side is getting both fuel & spark then about all that is left is low compression, or too much, or too little, air for the fuel amount sprayed in.

[Woodchips]

Thanks DR

I will have a look over on the left side for cable routing.

Just before I left on a ride today I started it up and it will idle with the fast idle advance but it is rough. I pulled the right injector connector off the top of the injector and there was no affect on the idle, that tells me that there is no signal to the injector !!!

On a previous test when I removed the right injector itself and ran the motor, fuel was coming out of the injector into a jar, and spark was present when the plug wire was pulled and grounded with a screwdriver to the head. I thought with both spark and fuel the there another issue causing the problem.

I think a new approach is required. Im thinking I’m going to remove the tank again and check everything I touched when I R and R’d the clutch, especially the wiring. When I think of all the possible issues caused by lifting the frame and replacing the air box and fuel lines, it is worth double checking my work.

Meantime, another trip is planned for tomorrow on my other 96 RT (215,000 K).

 

Stay tuned.

[dirtrider]

Morning Ron

 

I will have a look over on the left side for cable routing.-- Probably a good idea.

 

Just before I left on a ride today I started it up and it will idle with the fast idle advance but it is rough. I pulled the right injector connector off the top of the injector and there was no affect on the idle, that tells me that there is no signal to the injector !!!-- Not necessarily, it could be getting enough fuel but getting too much air for the amount of fuel bring injected. Or something is wrong with the injector (like a plugged inlet screen) so it could be  getting a signal but not actually injecting any fuel. Or it IS injecting fuel & IS getting enough air but something else is wrong with that cylinder like no spark, or low compression, or ????.

 

On a previous test when I removed the right injector itself and ran the motor, fuel was coming out of the injector into a jar, and spark was present when the plug wire was pulled and grounded with a screwdriver to the head. I thought with both spark and fuel the there another issue causing the problem.--  Still might be another problem. A spark externally to the engine might NOT  be enough spark to produce a spark inside a compressed cylinder (you need a bluish colored spark that will easily jump at least a 3/16" plug gap), if spark is yellow it is probably weak & won't spark under compression. Or the injector IS injecting fuel but not enough,,  a little injection spray looks like a lot so the spray could look good but actually not be enough to run that cylinder.

 

A quick test is to swap the injectors side to side to see if the problem moves to the other cylinder.

 

 

I think a new approach is required. Im thinking I’m going to remove the tank again and check everything I touched when I R and R’d the clutch, especially the wiring. When I think of all the possible issues caused by lifting the frame and replacing the air box and fuel lines, it is worth double checking my work.-- Probably not a bad idea but not needed if you verify that both side spark & fuel injection  being the same.  

 

Just keep in mind that the same coil sparks both sides equally so if one side is running OK then the primary to the coil must be working OK. But do check that both side spark plug wires are FULLY plugged into the coil. (very easy to have one plug wire partially pulled out of the coil after working on the under-tank things)

 

Same with the fuel injectors, both side injectors are powered by the same B+ circuit & triggered by the same computer circuit so  if one side is working OK then other side should work the same as long as no breaks in the wire to the bad side.

 

Things to check----- Check for R/H TB throttle arm to actually be resting on the idle stop screw (THIS MUST BE VERIFIED),, check for spark plug wires fully seated in the coil,, check for same amount of fuel spraying out of each side fuel injector (point  injectors into matching bottles then crank engine for a time period, then compare injection amounts,, check compression on non firing side/

[Woodchips]

Good morning D R

 

As usual your insight to solving the issue is REALLY appreciated.

I have set myself an Incentive of not going for a ride until I solve this problem 

I was thinking of switching the injectors from side to side before removing the tank again and double checking the throttle cables, that will be the first thing this morning.

 

Stay tuned.

 

[Woodchips]

Good afternoon D R

Just diving into the problem and the first thing I found is the right side butterfly is not reaching the stop. All cables appear to be where they are suppose to be. Im going to pull the intake tube on that side and see if the butterfly is closing as it should be.

This is my first try at posting a pic.

[dirtrider]

11 minutes ago, Woodchips said:

Good afternoon D R

Just diving into the problem and the first thing I found is the right side butterfly is not reaching the stop. All cables appear to be where they are suppose to be. Im going to pull the intake tube on that side and see if the butterfly is closing as it should be.

This is my first try at posting a pic.

 

 

Afternoon Ron

 

Is the choke OFF??????? if so then--------

 

More than likely THAT is your problem.

 

Are you SURE that the crossover cable outer housing is FULLY & PROPERLY seated  on both the L/H & R/H side (look very closely)

 

About the only thing that could cause the stop arm to be that far off the stop screw is  a tight crossover cable,  or a throttle plate that has come loose in it's slot  therefore jamming the throttle plate return.

 

You might try opening the R/H side throttle cam, then unhooking the cable to see if the TB arm will THEN seat on the stop screw.

[Woodchips]

Afternoon D R

Yes the fast idle was on at the first stop, after that was closed it ran a little bit better but still was very rough unless the throttle was opened a bit.

I backed the intake tubes out on both sides to check if the butterflies were closing and found they were tight against the inside of the throttle bodies. But the stop screw while closer, still does not touch the stop plate and I don’t think it has ever been touched.

 

(Note, the right throttle body has always had more “soot” then the left one.)

 

I then switched the injectors from side to side, there wasn’t much difference at idle but over 1500 or so it seemed to run smoother, again pulling the injector plug on the right side had no effect but pulling the left one killed the motor as before, strange !!!

I then checked the air screws and found the right one was about 1 ½ turns out less then the left one, so I opened the right one out to match the  left one and now the motor will run by itself if the “choke” is opened to keep it around the 1500 range. Both exhaust pipes get hot now as apposed to just the left one. 

I then pulled the new spark plugs and found the left one dark and a bit wet while the left one was a bit dark but dry !!!

Just having a coffee break to let the motor cool down and contemplating the next step.

 

……….to be continued

 

[dirtrider]

24 minutes ago, Woodchips said:

Afternoon D R

Yes the fast idle was on at the first stop, after that was closed it ran a little bit better but still was very rough unless the throttle was opened a bit.

I backed the intake tubes out on both sides to check if the butterflies were closing and found they were tight against the inside of the throttle bodies. But the stop screw while closer, still does not touch the stop plate and I don’t think it has ever been touched.

 

(Note, the right throttle body has always had more “soot” then the left one.)

 

I then switched the injectors from side to side, there wasn’t much difference at idle but over 1500 or so it seemed to run smoother, again pulling the injector plug on the right side had no effect but pulling the left one killed the motor as before, strange !!!

I then checked the air screws and found the right one was about 1 ½ turns out less then the left one, so I opened the right one out to match the  left one and now the motor will run by itself if the “choke” is opened to keep it around the 1500 range. Both exhaust pipes get hot now as apposed to just the left one. 

I then pulled the new spark plugs and found the left one dark and a bit wet while the left one (I presume that you mean right?) was a bit dark but dry !!!

Just having a coffee break to let the motor cool down and contemplating the next step.

 

……….to be continued

 

 

Afternoon Ron

 

On the 1100  single cable systems the R/H throttle arm doesn't NEED to contact the idle stop screw (it should but doesn't need to as the R/H side can hang closed on the crossover cable).

 

In fact when I set the balance on the 1100 single cable systems I back the R/H idle stop screw out so the throttle arm doesn't contact the stop screw, then AFTER I get the balance & idle RPM set correctly with the crossover cable  I then adjust the R/H idle stop screw to just very lightly contact the throttle stop arm at hot curb idle.

 

But the R/H side throttle plate does need to be closed enough to have an even cross side balance with the L/H side.

 

Do you have a U tube manometer or other vacuum balancing device??????

 

You really need to get a vacuum measuring device on that bike to see where your curb idle cross side balance is at.

[Woodchips]

Coffee finished.

That was what I was thinking should be my next step, I have a homemade vacuum setup that worked well on my other 96 RT.

The only other question I have concerns the installation of the repaired H.E.S. from

Cata Dan. He assures me the sensors were replaced and of course the wiring was replaced so I reinstalled the plate with the scratch marks lined up as before. I have not done anything with the TDC mark procedure that the Clymer manual talks about, could adjusting the plate position have any effect on the timing or does the CPU take care of that?

 

Back to work.

 

[Woodchips]

P.S. Is there a starting number of turns for the air screws?

[dirtrider]

6 minutes ago, Woodchips said:

P.S. Is there a starting number of turns for the air screws?

 

Afternoon Ron

 

A good starting place is 1-1/2 turns out from lightly seated.

 

You should also clean the BBS screw tips & air passages under them.

 

On your HES, that should be checked for proper timing at some point but it sparks & fuels both sides the exact  same so if it is running OK on the L/H side then that isn't you problem with the R/H side.   

[Woodchips]

I hooked up  the vacuum gauges and got each one readings the same at idle and about

3000 RPM.The only difference I noticed on the gauges is with the sudden closing of the throttle, the left gauge needle showed a momentary increase  in vacuum until idle, the right one did not move. Turning the screws in or out did not have any affect until they were completely seated. I left them both at 1 ½ turns out.

 

Time for another coffee.

[dirtrider]

17 minutes ago, Woodchips said:

I hooked up  the vacuum gauges and got each one readings the same at idle and about

3000 RPM.The only difference I noticed on the gauges is with the sudden closing of the throttle, the left gauge needle showed a momentary increase  in vacuum until idle, the right one did not move. Turning the screws in or out did not have any affect until they were completely seated. I left them both at 1 ½ turns out.

 

Time for another coffee.

 

Evening Ron

 

Does it run any better?

[Woodchips]

Yes it does, but not as smooth as it was before I touched things that didn’t need touching 😔. 

I’m going to increase the idle set screw to bring it back up to 11-1200 RPM. My other 1100 benefited by doing that.   

 

Supper time 👍

[dirtrider]

8 minutes ago, Woodchips said:

Yes it does, but not as smooth as it was before I touched things that didn’t need touching 😔. 

I’m going to increase the idle set screw to bring it back up to 11-1200 RPM. My other 1100 benefited by doing that.   

 

Supper time 👍

 

Evening Ron

 

OK, sounds like you are making progress.

 

Now that it is running better-------

 

Seeing as you have a single cable system do not use the choke to start the engine until you get the balance  re-checked.

 

Before starting use the twist grip to FULLY open the throttle about 4 or 5 times, then start without using the choke, then re-check your balance at idle & at part throttle.

 

Choke use can change the single cable to L/H TB pulley timing & that can effect  balance  adjustment.

[Woodchips]

Good evening D R

 

I will try that in the morning.

 

I appreciate your time on this.

 

Ron

[Woodchips]

Update to H.E.S. woes.

I did a compression test and got a reading of 170 PSI on both sides but that's as far as I got as I got called away from RT problems when the alternator and battery failed on my van, I'll try and get back to it in a day or so. It never seems to end. 

[Woodchips]

H.E.S. woes continued

Well after a couple of frustrating weeks trying everything I could think of and suggestions from D.R. to get the beast running, I took a break from it and took care of a couple of issues on my van and got in some day rides on my other 96RT (just turned 216,000K) and just plain took it easy.

This morning I went back to square one and pulled the tank off and rechecked all the electrical and fuel lines, plug wires, ran another compression test, and still it only wanted to run primarily on the left cylinder with the right one occasionally getting just warm.

As a final desperate move, I moved the H.E.S plate counter clockwise past my scratch marks as far as it would go and fired it up…….no change.

I then moved it clockwise as far as it would go and it ran much better and would actually idle on its own with the fast idle holding it around 1500 - 2000 RPM but still rough.

When I increase the throttle slowly it will pop and sputter up to around 3000 then it would increase smoothly as always. I figured I would then button up just what was needed to take it off the lift and run it around the block. 

Just as it did on the lift, once I got it up to around 2500 - 3000, it was like flipping a switch, it pulled very strongly and smoothly all the way through the gears, but still needed the throttle blipped or held around that 2000 RPM range to keep from stalling.

Its now back on the lift to get everything reinstalled, but I’m hoping someone has a suggestion for the low RPM roughness.

………..to be continued.

Ron

[dirtrider]

21 minutes ago, Woodchips said:

H.E.S. woes continued

Well after a couple of frustrating weeks trying everything I could think of and suggestions from D.R. to get the beast running, I took a break from it and took care of a couple of issues on my van and got in some day rides on my other 96RT (just turned 216,000K) and just plain took it easy.

This morning I went back to square one and pulled the tank off and rechecked all the electrical and fuel lines, plug wires, ran another compression test, and still it only wanted to run primarily on the left cylinder with the right one occasionally getting just warm.

As a final desperate move, I moved the H.E.S plate counter clockwise past my scratch marks as far as it would go and fired it up…….no change.

I then moved it clockwise as far as it would go and it ran much better and would actually idle on its own with the fast idle holding it around 1500 - 2000 RPM but still rough.

When I increase the throttle slowly it will pop and sputter up to around 3000 then it would increase smoothly as always. I figured I would then button up just what was needed to take it off the lift and run it around the block. 

Just as it did on the lift, once I got it up to around 2500 - 3000, it was like flipping a switch, it pulled very strongly and smoothly all the way through the gears, but still needed the throttle blipped or held around that 2000 RPM range to keep from stalling.

Its now back on the lift to get everything reinstalled, but I’m hoping someone has a suggestion for the low RPM roughness.

………..to be continued.

Ron

 

Evening Ron

 

That still has the ear marks of the throttle plates not being in sync at lower throttle openings.  Are you 100% positive that the throttle plates are opening at about the same angle at lower throttle settings?

 

It sort of sounds like the R/H throttle plate isn't closing far enough at idle & just above idle.  Is the R/H throttle body throttle  sitting on the throttle stop screw at no throttle??????????????????????????????????????  (is there slack in the R/H throttle cable at idle??????????) 

 

Or possibly a severely leaking throttle boot between the throttle body & cylinder head on the R/H side.  

[Woodchips]

Thanks for the quick reply D.R.

 

This morning I pushed the intake tubes back into the air box so I could check that the throttle plates were in sync with each other and closing fully at their stops. They are, and I am 100% positive the throttle cables are are riding in their respective groves as they should be.

With the tubes out of the way, I started it up and worked the throttle and with the throttle lock engaged I was able to confirm that the throttle plates close and open at the same time and the same amount. While it idles roughy and occasionally stalls I advanced the fast idle to the first notch which takes it up to around 2000 rpm and at that speed there was some visiable backfiring on the right side only. When opening the throttle to above 3000 the engine smooths out and there is no backfiring. 

Through all this, I have wondered if there is an issue with one of the intake valves on the right side, it ran smoothly with no backfiring before the tear down for the clutch replacement, and he only other component I touched was the H.E.S. as indicated earlier in my post.

Now that it runs, it has crossed my mind to take it over to the BMW dealer to see if they could find the problem with their diagnostic equipment. Its a course of action I am reluctant to take as I am retired on a tight budget and do not have a lot of faith in this particular dealership as on a couple of visits their comments on my 24 year old ride bordered on insulting.

…………to be continued 

 

 

[dirtrider]

1 hour ago, Woodchips said:

Thanks for the quick reply D.R.

 

This morning I pushed the intake tubes back into the air box so I could check that the throttle plates were in sync with each other and closing fully at their stops. They are, and I am 100% positive the throttle cables are are riding in their respective groves as they should be.

With the tubes out of the way, I started it up and worked the throttle and with the throttle lock engaged I was able to confirm that the throttle plates close and open at the same time and the same amount. While it idles roughy and occasionally stalls I advanced the fast idle to the first notch which takes it up to around 2000 rpm and at that speed there was some visiable backfiring on the right side only. When opening the throttle to above 3000 the engine smooths out and there is no backfiring. 

Through all this, I have wondered if there is an issue with one of the intake valves on the right side, it ran smoothly with no backfiring before the tear down for the clutch replacement, and he only other component I touched was the H.E.S. as indicated earlier in my post.

Now that it runs, it has crossed my mind to take it over to the BMW dealer to see if they could find the problem with their diagnostic equipment. Its a course of action I am reluctant to take as I am retired on a tight budget and do not have a lot of faith in this particular dealership as on a couple of visits their comments on my 24 year old ride bordered on insulting.

…………to be continued 

 

 

 

Afternoon Ron

 

The backfiring could be a valve issue but (IF) it ran geed before the trans work & you didn't touch the valve adjustment then a valve problem is unlikely. (if you even remotely suspect a valve issued then run a compression test).

 

It still sounds like a throttle plate timing issue but if you say that is OK then we will have to  move on to other things.

 

Have you verified that the R/H spark plug cable is FULLY plugged into the coil (that is easy to dislodge during trans removal)?????

 

Have you tried running it with the CCP removed from the fuse box (if not then try that).

 

 

 

 

[Woodchips]

Hi D.R.

 

As to the valve issue, I have not touched them this year. I have checked the compression twice during this episode and got 170 on both sides, twice. 

First thing in the morning I will double check the high tension leads. As to the CCP in the fuse box, I’m going to plead ignorance as to what that refers to 😔. 

Your help is really appreciated. 

Ron

[dirtrider]

27 minutes ago, Woodchips said:

Hi D.R.

 

As to the valve issue, I have not touched them this year. I have checked the compression twice during this episode and got 170 on both sides, twice. 

First thing in the morning I will double check the high tension leads. As to the CCP in the fuse box, I’m going to plead ignorance as to what that refers to 😔. 

Your help is really appreciated. 

Ron

 

 

Evening Ron

 

At 170 psi & even then that doesn't point to a valve issue.

 

The CCP is a coding plug (relay looking thingy) in the fuse box (see attached picture).  Removing that on the 1100 engine forces open loop operation so takes the o2 sensor out of the fueling control loop.

 

 

[Woodchips]

D.R.

I was wondering if there was a electronic test, I will try that in the morning and let you know the results. 

With rain in the forecast, the next best thing to riding is working on the Beemer. 

 

Ron

[Woodchips]

D.R.

just checked the fuse box on my RT. No CCP relay 😳

Canadian bike!!!

 

[dirtrider]

10 hours ago, Woodchips said:

D.R.

just checked the fuse box on my RT. No CCP relay 😳

Canadian bike!!!

 

 

 

Morning Ron

 

Canadian bike isn't a CCP qualifier, if an 1100  bike has a catalytic converter then it should have  a  CCP in the fuse box. If no cat then a CCP wasn't always installed but no-cat means that it would have had an idle trim pot on the L/H side about mid bike. (doesn't matter to your problem though as with NO CCP then the o2 sensor is not causing your problem).  No need to go any father down this road.

 

I re-read this thread (due to delays in following up it was getting kind of convoluted).

 

Definitely check that both spark plug wires are FULLY plugged into the coil. (lets get this verified).

 

Something that I read a few responses up kind of bothers me_____

 

I hooked up  the vacuum gauges and got each one readings the same at idle and about

3000 RPM.The only difference I noticed on the gauges is with the sudden closing of the throttle, the left gauge needle showed a momentary increase  in vacuum until idle, the right one did not move.--  Something doesn't seem right with this, that R/H side not moving on dropped throttle is not right. You might recheck this to see if it is still acting the same. You need to see a response on the R/H side  as you close the throttle (it should be close to the same vacuum side to side at idle, then somewhat track the same as you open & close the throttle & you should see about the same vacuum on each side as you work the throttle. If you have one side that is lacking, sluggish, or not tracking correctly then you need to find out why.   

 

 

[Woodchips]

Afternoon D.R.

 

I pulled the tank off and double checked both plug wires at the coil, and all was tight. I then  started it up again, and no change. I then removed the spark plugs and installed a set of used ones that were in the bike last fall to see if there was any difference, again no change. The right hand spark plug was quite dark (see Picture) compared to the left one. I took a short video of th bike running, but of course its too big to include here.

At this point I’m not sure what to try next, but I think I’ve monopolized enough of your time and expertise. If you can think of anything else I can try, please let me know.

 

Ron 

[dirtrider]

28 minutes ago, Woodchips said:

Afternoon D.R.

 

I pulled the tank off and double checked both plug wires at the coil, and all was tight. I then  started it up again, and no change. I then removed the spark plugs and installed a set of used ones that were in the bike last fall to see if there was any difference, again no change. The right hand spark plug was quite dark (see Picture) compared to the left one. I took a short video of th bike running, but of course its too big to include here.

At this point I’m not sure what to try next, but I think I’ve monopolized enough of your time and expertise. If you can think of anything else I can try, please let me know.

 

Ron 

 

 

 

Evening Ron

 

I will think on this a little more (look back here in a while)

 

In the mean time put your vacuum gauge set back on the bike & see if you can understand that gauge reading discrepancy  that you had.

 

 

[Woodchips]

Thanks D.R.

I can see the value in tracking down the imbalance on the vacuum gages, and any intake leaks. 

........to be continued 🤔

Ron

 

 

 

[Woodchips]

Good afternoon D.R.

 

Well Its been almost 7 months since I left the 96RT1100 on the lift with the unsolved intake backfiring problem on the right cylinder only. I enjoyed a number of great rides with my other 96RT1100 right up until the end of November with the odometer reaching 220,000 Kilometres. I got out for the first short ride of this year last week then the snow and cold returned so it was back to trying to solve the mystery of the right side backfiring.

Over the winter my son made the timing light box from the online plans and we managed to get the beast running to the point that it would idle with the fast idle set to around 1500 to 2000 RPM. I then played with the H.E.S. position and air screw settings with attached vacuum gauges and got it to idle just under 1500 but still backfiring.

This morning I thought I would try a new approach to eliminating a possible fuel issue. I switched the injectors side to side with no difference. Next with the motor running at its lowest RPM, I introduced a stream of propane from my soldering bottle directly into the right TB intake (both tubes pulled back), and the RPM's rose to approximately 2000 with no backfiring. When I removed the propane, the backfiring resumed. I followed the same procedure on the left side but  there was no change in RPM?

I have run out of things to try and have thought of switching the H.E.S. from my running RT to this one but thought I would update you and seek your wisdom once again. I have a very good video of what I did with the propane this morning but don’t know how or if I can get it to you on the forum.

As usual, any suggestions would be appreciated.

 

Ron

 

 

 

[dirtrider]

11 minutes ago, Woodchips said:

Good afternoon D.R.

 

Well Its been almost 7 months since I left the 96RT1100 on the lift with the unsolved intake backfiring problem on the right cylinder only. I enjoyed a number of great rides with my other 96RT1100 right up until the end of November with the odometer reaching 220,000 Kilometres. I got out for the first short ride of this year last week then the snow and cold returned so it was back to trying to solve the mystery of the right side backfiring.

Over the winter my son made the timing light box from the online plans and we managed to get the beast running to the point that it would idle with the fast idle set to around 1500 to 2000 RPM. I then played with the H.E.S. position and air screw settings with attached vacuum gauges and got it to idle just under 1500 but still backfiring.

This morning I thought I would try a new approach to eliminating a possible fuel issue. I switched the injectors side to side with no difference. Next with the motor running at its lowest RPM, I introduced a stream of propane from my soldering bottle directly into the right TB intake (both tubes pulled back), and the RPM's rose to approximately 2000 with no backfiring. When I removed the propane, the backfiring resumed. I followed the same procedure on the left side but  there was no change in RPM?

I have run out of things to try and have thought of switching the H.E.S. from my running RT to this one but thought I would update you and seek your wisdom once again. I have a very good video of what I did with the propane this morning but don’t know how or if I can get it to you on the forum.

As usual, any suggestions would be appreciated.

 

Ron

 

 

 

 

Afternoon Ron

 

Kind of conflicting info so that will make things a bit more difficult to diagnose. 

 

It should have perked up when you introduced propane to either side so that is a bit puzzling.

 

At first thought it sounds like the R/H side might be running pretty lean so make sure the R/H side injector is actually triggering correctly (a 'noid' light is best for this).

 

Or possibly you have a slightly burnt valve on one  side ( a home type leak-down test is best to verify this)-- Piston at TDC on compression stroke, air fitting  in upper spark plug hole, then use your air compressor to blow some air into each cylinder & see IF/WHERE the air comes out. If out the intake then possibly a burnt intake valve, if out the exhaust then possibly a burnt exhaust valve. 

 

It actually doesn't have to be a burnt valve as small piece of carbon caught between a valve & valve seat will act the same way.

 

Is it actually backfiring (popping back into the intake) or is it a post-fire popping out of the muffler/exhaust?

 

 

[Woodchips]

Thanks DR 

I too am leaning towards a burnt intake valve, I tried building my own leak down tester over the winter but did not succeed so will try just introducing compressor air at TDC on the compression stroke as you suggest.

I too was puzzled as to why the RPM did not increase on the left side?

[Woodchips]

BTW, a number of times throughout this issue I have pulled the injector connector and the motor will stall and or really run rough and then perk up when reconnected. Is there a specific “noid” tester for these injectors, the local auto supply store carries a kit of 6 that includes GM, Ford, GEO, and a Bosch PFI.

Thanks 

Ron

[dirtrider]

1 hour ago, Woodchips said:

BTW, a number of times throughout this issue I have pulled the injector connector and the motor will stall and or really run rough and then perk up when reconnected. Is there a specific “noid” tester for these injectors, the local auto supply store carries a kit of 6 that includes GM, Ford, GEO, and a Bosch PFI.

Thanks 

Ron

 

Evening Ron 

 

Yes, there is a specific noid light tester for your injector connector, you need to match the noid light up to your injector harness connector.  

[Woodchips]

Thanks DR, the saga continues