Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet with the UCE engine => Topic started by: Sectorsteve on November 10, 2013, 12:26:55 pm

Title: spark plus seem to have changed?
Post by: Sectorsteve on November 10, 2013, 12:26:55 pm
Ive been using the plugs most of us are using. the BPR6ES.
I bought 2 the other day after some erratic iddling , cut outs etc. Usually i jut screw the cap off these plugs to make em fit the plug lead, but these ones didnt have the screw off section. instead the whole stem came out of the spark plug.
anyone know anything about this?
Title: Re: spark plus seem to have changed?
Post by: GreenMachine on November 10, 2013, 03:50:18 pm
Nope, sounds like a defect..Take it back and get another one and inspect it while u r there...
Title: Re: spark plus seem to have changed?
Post by: Craig McClure on November 10, 2013, 05:00:50 pm
Sounds familiar. The first one I bought on line, did not have a removable top spindle shaped nut. After learning that there are 2 types, I carefully ground down the spindle section small enough to get my plug wire on it & used it until I found the correct one. Now its a spare.
  I imagine if someone thought the top was supposed to come off,  & twisted hard enough with a pliers, it could come apart.
Title: Re: spark plus seem to have changed?
Post by: heloego on November 10, 2013, 05:35:11 pm
Sounds like the threaded spindle sheared from over-tightening at the plant, and QA missed it.
Yeah, get a new one.  :)
Title: Re: spark plus seem to have changed?
Post by: rvcycleguy on November 10, 2013, 07:23:36 pm
The plug may have been returned to the store unopened after a customer determined the screw top did not come off?  Take it back and inform them of the issue. 
Title: Re: spark plus seem to have changed?
Post by: barenekd on November 10, 2013, 07:34:12 pm
They make both types of plugs. I had some of the fixed tip ones here, but I must've used them. My GB500 would take the others. There is a stock number on the boxes, 7131, that the the removable tips on them. I'm not sure what the fixed tips have. I didn't notice any number on the plugs that could differentiate them.  Just check them before you buy them.
Bare
Title: Re: spark plus seem to have changed?
Post by: D the D on November 11, 2013, 02:26:42 am
Like Craig and Bare both said:  NGK and other brands make both types and you have to check which you're getting.  I've found both and had to return mail order ones that were solid.
Key to look at?  Is the end of the threaded rod viewable from the top or the cap?  If not, it's solid - the screw on caps are hollow tubes with threads, not a closed over cap.
Title: Re: spark plus seem to have changed?
Post by: Sectorsteve on November 11, 2013, 10:22:22 am
thanks guys. ive put the bosch twin electrode back in. the bikes running better than it has for months with this one back in for now. its still pretty new.
Title: Re: spark plus seem to have changed?
Post by: Craig McClure on November 11, 2013, 02:55:09 pm
Hey Steve, Call around your local auto parts stores. That NGK plug is very common. I ordered my first (wrong Type) on line - turns out my local auto parts store had the correct ones even cheaper, so I bought a few. Original twin electrode plugs aren't as good - trust me.
Title: Re: spark plus seem to have changed?
Post by: barenekd on November 11, 2013, 06:51:45 pm
You don't realize how many  problems you actually have with the Bosch, until you put the NGK in!
Bare
Title: Re: spark plus seem to have changed?
Post by: gashousegorilla on November 11, 2013, 07:48:20 pm
  Or.... one could just change their spark plug boot to the larger top terminal type, and never have to worry about it again. So what ever comes in the box... either a fixed terminal or thread terminal adapter would work fine.
Title: Re: spark plus seem to have changed?
Post by: Royalista on November 11, 2013, 09:26:50 pm
I know everyone is adamant about it.
Just for the record, I stick with the OEM plug.  :-[

My engine runs smoothly, no hickups. It starts under every condition alla prima. First plug served 23000kms before showing signs of age, and is duly replaced with a younger brother. It too performs flawlessly. :)

I mentioned I ran a test for 1000kms with the BRP6ES plug. I was apalled by its condition. It came out overly dirty.  :o
It was a relief having faithful back in.
My small poll came to this preliminary conclusion: unless you are subject to fuel contaminated with ethanol and having poor results from the plug a NGK one can bring relief to the problem.
Sjeesh. There was a time when one had to move to a third world country to have questionable fuel.  ::)
Title: Re: spark plus seem to have changed?
Post by: Ducati Scotty on November 11, 2013, 09:36:32 pm
I'd say that if you're not having problems with a wandering idle speed or rough running and stalling, especially during  warmup, you don't need an NGK plug.  If you are having trouble getting your engine to run smoothly it's one of the first things to try.

Scott
Title: Re: spark plus seem to have changed?
Post by: Royalista on November 11, 2013, 09:41:58 pm
+1
Yep, I totally agree to that.
There will be plenty of other issues to entertain us.  ;D
Title: Re: spark plus seem to have changed?
Post by: gashousegorilla on November 11, 2013, 10:13:37 pm
    I agree. I'm not one for the mass NGK plug craze. They are a good plug though. And I use them.... because they are locally available.  But  I've used autolite and champion as well for my needs, and they are fine.  I never had a problem with the stock Bosch plug either. 

   My guess is.... even though the NGK and Bosch plug heat ranges work out in the cross reference charts, the Bosch plug is actually a little colder. Because when people have these symptoms, they seem to be issues you would have with using a plug that is too cold for the way their bike is set up and tuned.  It could also be , that the people who are having issues with the stock plug, have a slightly higher base TPS setting .....

 I'm thinking the proper heat range for your particular bike is more at play here , could be a NGK with a heat range of 6 or 7 for example ? But more so then the brand of plug you use......
Title: Re: spark plus seem to have changed?
Post by: Ducati Scotty on November 11, 2013, 10:24:07 pm
6 is what most people use, 7 is cooler and 5 is hotter.  For NGK anyway, I think most other brands higher numbers mean hotter.

I swapped out for an NGK because my idle hunted, especially when cold, and this helped immediately.  I've used both a 6 and a 7 without issue.  I'm sure any brand, including Bosch, could be used so long as the heat range is right and it's a single electrode.  I think it's the dual electrode of the Bosch that causes the problems.  Aside from that, it's basically the same as every other plug in production.

Scott
Title: Re: spark plus seem to have changed?
Post by: gashousegorilla on November 11, 2013, 10:56:33 pm


  I think it's the dual electrode of the Bosch that causes the problems.  Aside from that, it's basically the same as every other plug in production.

Scott

  That could very well be Scott..... but I don't know why.  I don't think there is any advantage for a duel ground strapped plug. It's gonna ark at the path of least resistance.....  Maybe the duel ground straps acts to dissipate heat quicker,like a heat sink, so it acts like a colder plug. Just a guess though....
Title: Re: spark plus seem to have changed?
Post by: Ducati Scotty on November 11, 2013, 11:19:16 pm
As I understand, it's used in aviation and other critical applications to be redundant.  If one electrode melts or falls off, there's another there and the motor keeps turning.  I'm not sure if they chose it on the RE for emissions or some other purpose, but like lots of others here, as soon as I swapped it for an NGK my bike ran way better.  Solid idle and stopped stalling.

Scott
Title: Re: spark plus seem to have changed?
Post by: gashousegorilla on November 12, 2013, 12:52:58 am
As I understand, it's used in aviation and other critical applications to be redundant.  If one electrode melts or falls off, there's another there and the motor keeps turning.  I'm not sure if they chose it on the RE for emissions or some other purpose, but like lots of others here, as soon as I swapped it for an NGK my bike ran way better.  Solid idle and stopped stalling.

Scott

    Makes sense .   Curious Scott, did you ever have an opportunity to check your base TPS voltage from the factory ? And if so, what was the reading ?  Mine was low....  Under .6v  But no problem with the stock Bosch plug at the time.
Title: Re: spark plus seem to have changed?
Post by: JVS on November 12, 2013, 12:56:04 am
My idle TPS from factory was 0.61V. Did change it once to make it a bit 'richer', but returned it back to 0.61V. Been like that ever since.
Title: Re: spark plus seem to have changed?
Post by: gashousegorilla on November 12, 2013, 01:47:17 am
My idle TPS from factory was 0.61V. Did change it once to make it a bit 'richer', but returned it back to 0.61V. Been like that ever since.

   Any issues with the stock plug  JVS ? 
Title: Re: spark plus seem to have changed?
Post by: JVS on November 12, 2013, 02:06:15 am
To be honest, even with constant cleaning of the stock plug, it would end up looking quite fouled after every 300km or so. That is with the stock TPS voltage and rides lasting more than 20-30mins or even longer rides. The bike would run okay and never really showed any signs of trouble if I remember correctly. Only the idle was a bit erratic. And a lot of soot over the double electrodes, not sure why.

Then I swapped to the BPR6ES after reading the feedback given here on the forum. The idle RPM had increased staight after the swap, so I decreased it. After that, everytime I've taken it out to clean it up etc on service intervals as highlighted in the manual or just for inspection, the electrode part has never shown signs of running too rich or too lean. Always has shown me light brown/tannish tinge on the electrode, with carbon deposits only on the outer ring of the plug (Surrounding the electrode). I'm running the EFI silencer with the mechanical baffle out, leaving the perma-perforated baffle in it. The system has adjusted to it well, with rare-occasional backfiring.
Title: Re: spark plus seem to have changed?
Post by: gashousegorilla on November 12, 2013, 03:06:03 am
To be honest, even with constant cleaning of the stock plug, it would end up looking quite fouled after every 300km or so. That is with the stock TPS voltage and rides lasting more than 20-30mins or even longer rides. The bike would run okay and never really showed any signs of trouble if I remember correctly. Only the idle was a bit erratic. And a lot of soot over the double electrodes, not sure why.

Then I swapped to the BPR6ES after reading the feedback given here on the forum. The idle RPM had increased staight after the swap, so I decreased it. After that, everytime I've taken it out to clean it up etc on service intervals as highlighted in the manual or just for inspection, the electrode part has never shown signs of running too rich or too lean. Always has shown me light brown/tannish tinge on the electrode, with carbon deposits only on the outer ring of the plug (Surrounding the electrode). I'm running the EFI silencer with the mechanical baffle out, leaving the perma-perforated baffle in it. The system has adjusted to it well, with rare-occasional backfiring.

  Interesting JVS .  Sounds like it is about perfect now. And particularly the way your idle speed increased ,with what I think is the hotter NGK 6 plug.  I actually think the stock Bosch plug acts more like an NGK with a colder heat range of 8 .... 

  As to why ?  My bet is it's what your TPS is set at.  Yours was .61v, mine was at .57v...  Higher voltage, richer across the range. Like when you start the bike on that rich idle, before the 02 sensor heats up and it's in closed loop.  Lower TPS voltage... leaner across the range.  So I could get away with a colder plug.   I think your AFR's were a little too rich, for the heat range of the stock plug.  Not getting to the self cleaning temp that the plug should be at.    Where as in my case it was.   It's what i'm thinking anyway...... And I'm thinking based on that, we should be fine with an NGK with a 6 OR 7 heat range.  BTW, when the bike was stock, I used a 7 in the summer and a 6 in the winter.