Author Topic: Spark Plug for Classic C5 (Read 22316 times)

gillonnet · **on:** September 13, 2011, 02:23:18 am

Hi, What is the right replacement for spark plug for my classic chrome c5. I'm getting hard time to find right one.
And , Is it right to clean exhaust sensor after some time???
thanks,
good day
Amandeep Singh Gill

GSS · **Reply #1 on:** September 13, 2011, 03:24:20 am

Amandeep,
NGK BPR6EIX Iridium works great on the C5. I wouldn't worry about cleaning the exhaust sensor.
Regards,

GSS

Arizoni · **Reply #2 on:** September 13, 2011, 05:25:57 am

gillonnet: If you can't get the iridium plug you will find that the lower cost regular NGK BPR6ES will (in my opinion) work just as well.

The BOSCH WR7 DDC4 plug that the fuel injected UCE bikes come with is, to the best of my knowledge, not available in the U.S.

Even if it were I would stick with the NGK.

Shortly after getting my G5 Deluxe I noticed that there would be mis-fires while riding at a smooth 40 MPH, some of them being so noticeable that the bike would jerk. I mentioned it here on the forum and was advised to get the NGK BPR6ES, which the local O'Rielly's wanted the princely sum of $2.45 for.

I bought it and installed it and my idle improved and the mis-fire has never returned.

mbevo1 · **Reply #3 on:** September 13, 2011, 02:46:30 pm

Quote from: GSS on September 13, 2011, 03:24:20 am

Amandeep,
NGK BPR6EIX Iridium works great on the C5.

I'm using the same. Noticable improvement to the idle. Works fine.

Mike and S&S in Michigan

TWinOKC · **Reply #4 on:** September 13, 2011, 03:08:38 pm

Quote from: Arizoni on September 13, 2011, 05:25:57 am

gillonnet: If you can't get the iridium plug you will find that the lower cost regular NGK BPR6ES will (in my opinion) work just as well.

The BOSCH WR7 DDC4 plug that the fuel injected UCE bikes come with is, to the best of my knowledge, not available in the U.S.

Even if it were I would stick with the NGK.

Shortly after getting my G5 Deluxe I noticed that there would be mis-fires while riding at a smooth 40 MPH, some of them being so noticeable that the bike would jerk. I mentioned it here on the forum and was advised to get the NGK BPR6ES, which the local O'Rielly's wanted the princely sum of $2.45 for.

I bought it and installed it and my idle improved and the mis-fire has never returned.

+1 I thought the NGK BPR6ES was the preferred one. I have one in my bike, works great.

Terry

Ducati Scotty · **Reply #5 on:** September 13, 2011, 06:23:21 pm

+1 with caveat. I've been using the NGK BRP6EIX Iridium plug and it works well. I have noticed that it is a little white wo I've dropped to a one notch cooler plug and skipped the Iridium this time: BPR7ES. I agree with folks here that Iridium vs. standard probably doesn't matter but now I'll know for sure. Even if it does matter, the Iridium plugs are only about $10US, not going to break the bank.

Don't clean the O2 sensor. If the bikes running fine then it's fine,

Scott

prof_stack · **Reply #6 on:** September 13, 2011, 06:50:49 pm

Quote from: Ducati Scotty on September 13, 2011, 06:23:21 pm

+1 with caveat. I've been using the NGK BRP6EIX Iridium plug and it works well. I have noticed that it is a little white wo I've dropped to a one notch cooler plug and skipped the Iridium this time: BPR7ES. ...Scott

How about a primer: If the plug is white, then choose the ____ because ____.
If the plug is black, then choose teh ___ because ____.

Would a different heat range plug have any effect on the OEM pipe getting blue sooner than later?

Thanks.

Ducati Scotty · **Reply #7 on:** September 13, 2011, 06:57:23 pm

I don't think so. White means the plug itself is getting too hot. This can sause pre-detonation. Though the NGK is the same heat range as the stock Bosch the Bosch was tan ans this plug is white. If all else in the engine is ok, and I believe it is, then I need a cooler plug. Could be my riding style, the gas I use, lots of things. Check your plug. If it's a light tan it's just fine for you and don't worry about what I'm using

Here's some good reading:
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp?mode=nml
http://www.ngksparkplugs.com/tech_support/spark_plugs/index.asp?mode=nml
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/index.asp?mode=nml

Scott

GSS · **Reply #8 on:** September 13, 2011, 09:57:58 pm

Quote from: Ducati Scotty on September 13, 2011, 06:23:21 pm

+1 with caveat. I've been using the NGK BRP6EIX Iridium plug and it works well. I have noticed that it is a little white wo I've dropped to a one notch cooler plug and skipped the Iridium this time: BPR7ES. I agree with folks here that Iridium vs. standard probably doesn't matter but now I'll know for sure. Even if it does matter, the Iridium plugs are only about $10US, not going to break the bank.

Don't clean the O2 sensor. If the bikes running fine then it's fine,

Scott

I will have to check mine. BPR8EIX was definitely cold and had lots of carbon deposits when I had that in for a few days. The BPR6EIX is working great and definitely a huge step up from the OEM Bosch. Totally fixed the rough idle and occasional stalls that I had when the bike was new. The 7 will be probably be just fine.

Ducati Scotty · **Reply #9 on:** September 13, 2011, 10:29:44 pm

Iremember someone, or maybe several people, saying the 8 was too cold for the UCE engines. I was glad to see the 7 was available and in stock at the local auto shop to boot!

Scott

Arizoni · **Reply #10 on:** September 13, 2011, 11:15:48 pm

Folks should notice in the
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp?mode=nml
link that white is not bad. IMO, with modern unleaded gas it can almost be considered ideal. A light gray is best with the light tans showing up depending on what additives are in the fuel at your gas station.

The "Too Hot" insulators will be glassy or glazed looking often with blisters on them.

Bottom line? A dull white, gray or light tan = GOOD
A dull dark brown to black = BAD

higgins · **Reply #11 on:** September 13, 2011, 11:36:36 pm

If you want the NGK iridium, I think you need to order NGK IRIDIUM IX Spark Plug BPR6EIX # 6637, rather than NGK IRIDIUM IX Spark Plug BPR6EIX # 3903. The former has a removable terminal nut which I need for my B5. Not sure if G5/C5 have a different terminal connector.

Ducati Scotty · **Reply #12 on:** September 13, 2011, 11:58:14 pm

We do need the removable terminal nut, the stock plug wire is for small terminals, not large. I guess I just got lucky and got the right one.

Zoni, thanks for pointing out that white may be ok. I should read the links I post more carefully

The side electrode looked ok, not melted or anything, just white and peeling a bit. I'll take a closer look at the whole plug. Maybe it's not as bad as I thought. I just know that the stock plug was a perfect tan and this one ain't.

Scott

higgins · **Reply #13 on:** September 14, 2011, 12:09:52 am

As always, better to lucky than to be good.

Ducati Scotty · **Reply #14 on:** September 14, 2011, 05:44:12 pm

I swapped out the plug last night. On closer inspection it's not really bad. White or very light gray, no glazing or erosion of the electrodes, really not that bad.

I was mostly concerned because it was not the perfect tan that the stock plug was and I seem to get a little pinging up hills in mid range RPM. I'll ride the new plug for a few days and see how it goes. It did drop the idle just a smidgen but seems as stable as the EIX, so it appears both Iridium and standard can help stabilize the wandering idle.

Scott

BRADEY · **Reply #15 on:** September 16, 2011, 07:42:30 am

Too little riding (read short distance) may also result in black sooty plugs. The carbon usually cleans automatically after a long ride..

Ducati Scotty · **Reply #16 on:** September 20, 2011, 04:22:35 am

So here are some pics:
http://www.enfieldmotorcycles.com/forum/index.php?action=gallery;sa=view;id=3660
http://www.enfieldmotorcycles.com/forum/index.php?action=gallery;sa=view;id=3661

The plugs pictured are both NGK. The BPR6EIX (small iridium electrode) has maybe 1000 miles on it, the BPR7ES (standard electrode) has about 100. You can see here the color on the 6 is a lighter. It actually looks white in person. The 7 has a darker, rich gray color. You can also see the sort of bubbly deposits forming on the 6. I don't think anything's getting hot enough to glaze or pit but it doesn't look goo. I think the 6 was just a little too hot for my engine even though it's the exact same heat range as the stock Bosch. I also feel like I was getting just a little pinging with the 6 on low to mid rnage RPM hill climbs. The color on the 7 (one notch cooler) is better IMO and I also don't get the pinging. The engine sounds like it's running 'cleaner' if that makes any sense.

I'll be keeping an eye on the 7, it's only got a few miles but the 6 always had a stark white color to it since I started using it. I may need to switch back as the cold weather is coming on in my part of the world.

Also, both plugs (standard and iridium) seem to have the same stabilizing effect on the idle speed, which tended to wander a bit with the Bosch plug. So you can get either the ES or the more expensive EIX and get the same benefit. I'm thinking of getting the 7EIX just to get a straight apples to apple comparison.

Scott

BRADEY · **Reply #17 on:** September 20, 2011, 09:30:36 am

Mine was fitted with a Bosch Platinum WRDP single electrode plug by the RE service engineer. I forget whether the heat range was 7 or 8. The plug no. would thus be WR7DP or WR8DP...........what I am trying to say is, its perfectly tan (from one side, which probably is the flame side of the plug, and white on the other side)....

The bike occassionaly shows slow revs hicups......but I am quite happy with it....!!

Ducati Scotty · **Reply #18 on:** September 21, 2011, 06:29:33 pm

I switched back to the 6 for a couple of days, then to the 7 again today. The 7 idles just a tad lower and does make for a quieter, cleaner sounding engine all around, especially on low to mid RPM hill climbs. I also noticed slightly less high frequency vibration at 65mph in 5th.

Scott

prof_stack · **Reply #19 on:** September 21, 2011, 08:58:48 pm

Quote from: Ducati Scotty on September 21, 2011, 06:29:33 pm

I switched back to the 6 for a couple of days, then to the 7 again today. The 7 idles just a tad lower and does make for a quieter, cleaner sounding engine all around, especially on low to mid RPM hill climbs. I also noticed slightly less high frequency vibration at 65mph in 5th.

Scott

Sounds interesting, but I think more data is needed. Thanks.

Ducati Scotty · **Reply #20 on:** September 21, 2011, 10:18:41 pm

I agree. I think the 7 may not be right for every bike or every riding style. Still, it didn't end up covered in carbon after a short while like someone reported the 8 did. I do remember one other member posting that his mechanic said his BPR6 plug was too hot for his bike. It's subtle but the bike seems to run better with the 7 than the 6 for me. Anyone else who wants to try, it only costs $2.50 US.

Scott

prof_stack · **Reply #21 on:** September 22, 2011, 12:33:51 am

I'll post Dirk's final trip report later today, but one thing he said was that changing the OEM Bosch plug to the NGK BPR6ES plug I gave him made everything perfect with the running of his B5, which was stumbling upon acceleration.

I will try the 7 version in my C5 and see how it looks.

Ducati Scotty · **Reply #22 on:** September 22, 2011, 12:58:24 am

No doubt the NGK (6 or 7) seems to cure the idle wander and low speed stumbles that some people get with the stock Bosch. I think there have already been several reports of NGK '8' plugs running too cold. But I think 6 or 7 may either both be acceptable or may be a choice based on the engine/rider/riding style/ambient temperature.

Thanks for trying a 7 Stack. It'll be nice to see what you find. Post a pic of the two side by side if you can after you get a few miles on the 7.

Scott

eda1bulletc5 · **Reply #23 on:** April 19, 2012, 04:57:39 pm

Hello to all RE brothers!

I would please like to know which iridium spark plug to go with on a C5 UCE; is it
- BPR6EIX
- BPR7EIX

I am planning to change my stock C5 plug.

Please advice.

Thanks.

Ducati Scotty · **Reply #24 on:** April 19, 2012, 06:01:53 pm

I'd try the 6 first and keep an eye on it. If it's too white (too hot) go to the 7, a notch cooler. Also, the standard plug seems to work as well as the Iridium and only costs about $2.50 vs. about $10 for the iridium. Remember to gap it correctly no matter which plug you get.

Scott

eda1bulletc5 · **Reply #25 on:** April 19, 2012, 06:55:51 pm

Scotty,

Thanks for the input!

Yes, I would have to properly gap it...What is the recommended spark plug gap for C5 UCE engines?

rbelyk · **Reply #26 on:** April 19, 2012, 07:21:15 pm

the iridium plugs come gapped correctly, at least mine did
I read in another post that they are really easy to break if you try and gap them.
cheers

Ducati Scotty · **Reply #27 on:** April 19, 2012, 07:27:43 pm

Mine didn't, it was set to something like 3X the gap it should have. It was very easy to gap. I think some of the first precious metal plugs that came out many years ago were not supposed to be gapped. The new ones, some are and some aren't. I think these are fine.

Scott

singhg5 · **Reply #28 on:** April 19, 2012, 07:34:59 pm

Quote from: eda1bulletc5 on April 19, 2012, 06:55:51 pm

Yes, I would have to properly gap it...What is the recommended spark plug gap for C5 UCE engines?

This is SinghG5, not Scotty to share my experience with you.

Iridium plugs are expensive and provide no real advantage to its regular counterparts. A NGK BPR 6ES has been used by many riders. No need to change any gap - just put it straight into the engine. I have used all kinds of spark plugs over 3 years for my G5 and the above mentioned is my favorite. Never changed any gap and I get 70 to 71 miles a gallon (US) even today - just verified this week to see how is bike doing

.

If someone is very picky, use BPR6ES for winter or for slow riding and BPR7ES for hot days or for long high speed riding. That is a bit overkill if you have a set riding style. If you live in some place as me (New Jersey), go for 6, and if in a hotter place, try a 7.

corey roy · **Reply #29 on:** April 19, 2012, 08:31:46 pm

Here is a good reference about spark plugs, straight from NGK's website.

http://www.ngksparkplugs.com/tech_support/spark_plugs/index.asp?mode=nml

Ducati Scotty · **Reply #30 on:** April 19, 2012, 09:17:31 pm

I agree with Singh, get the cheaper plug and blow the savings on women and booze!

Corey, thanks for posting NGK's page. They've got some very nice info.

Scott

eda1bulletc5 · **Reply #31 on:** April 19, 2012, 10:02:16 pm

Hi Folks!

These are good information!

I checked with RE dealer at SoCal and they recommended going either with BPR6EIX or BPR6ES doesn't matter.

With the iridium the longevity is better compared to regular spark plugs; might most probably go with BPR6EIX. Cost difference is not too much

Thank you all...

Also, as I start using the RE C5 more I might have more questions, so please bear with me!!

Regards,
Sajiv

GSS · **Reply #32 on:** April 19, 2012, 11:38:40 pm

Quote from: eda1bulletc5 on April 19, 2012, 10:02:16 pm

With the iridium the longevity is better compared to regular spark plugs; might most probably go with BPR6EIX. Cost difference is not too much.

Good decision. I took mine out after 1000 miles to take a look. Perfect light tan color, no carbon deposits, well worth the couple of extra bucks.

You will not go wrong with the 7 suggested by Scott either. I had an 8ES for about 50 miles while I was waiting for the 6EIX and it came out coated with carbon fluff.

GSS

corey roy · **Reply #33 on:** April 20, 2012, 02:15:56 am

I tend to run my C5 long and hard at high speeds. Occasionally, after being at high RPMs in 5th gear for a while (30+ minutes) I notice a slight misfire feeling. Could it be my plug is too hot at that point? Would bumping up to the 7 from the 6 make a difference there?

Ducati Scotty · **Reply #34 on:** April 20, 2012, 02:48:03 am

Yup.

eda1bulletc5 · **Reply #35 on:** April 26, 2012, 05:27:02 pm

Hi Folks,
I did my first service on my 2011 C5 and got the spark plug changed to BPR6EIX. I can definitely see a much consistent RPM during idling, with the stock plug I used to notice the RPM changing quite a bit.
Also, changed the air filter to K&N filter RO-5010 http://www.knfilters.com/search/product.aspx?Prod=RO-5010

The bike runs much better and the lower/mid range torque seems better.

I am also waiting for this after market exhaust to arrive, I believe this was suggested on one of the threads in this forum, http://bulletwala.com/exhaust-systems/silencers/new-chrome-royal-enfield-500cc-electra-silencer-assly.html

Lets see how it will work!

Thanks guys!

barenekd · **Reply #36 on:** April 26, 2012, 06:30:48 pm

My BPR6ES after 8000 miles. This is the first time I've taken it out since the original installation. Looks good, works good, it's going back in.
Bare

Ducati Scotty · **Reply #37 on:** April 26, 2012, 06:45:06 pm

What?!? And leave well enough alone? Dude, that's not how we operate around here.

barenekd · **Reply #38 on:** April 26, 2012, 06:56:33 pm

OK,so I dropped the gap a couple of thou.
Bare

GreenMachine · **Reply #39 on:** April 26, 2012, 07:28:57 pm

What?!? And leave well enough alone? Dude, that's not how we operate around here.

So true and funny as hell..

Arizoni · **Reply #40 on:** April 26, 2012, 10:53:41 pm

Another post about the spark plug cap and how it attaches to the wire made me go out to look at mine.

While I was going out there I thought that maybe I should take a look at the condition of the plug because it's been over 4000 miles since I last looked at it.

It is a NGK BPR6ES plug. The $2.50 kind.

It looks just like bare's plug. The gap is still set correctly and I'm a happy camper.
Just for giggles, I did replace it with a brand new plug of the same type but I am keeping the old one in the box in case I ever need it.

Lwt Big Cheese · **Reply #41 on:** April 27, 2012, 08:51:18 am

Quote from: Ducati Scotty on April 26, 2012, 06:45:06 pm

What?!? And leave well enough alone? Dude, that's not how we operate around here.

You have to modify until it becomes unreliable then bitch about the un-reliablity!!!

barenekd · **Reply #42 on:** April 27, 2012, 06:04:51 pm

Quote

You have to modify until it becomes unreliable then bitch about the un-reliablity!!!

+1 to that!

dynamyt · **Reply #43 on:** July 09, 2012, 03:57:37 am

I just swapped out the Bosch plug for the NGK BPR6ES in my G5 Bullet. Wow! Idle is smoother, acceleration is better, starts easier. This is a no brainer... just do it!

DEWEY · **Reply #44 on:** July 09, 2012, 05:34:36 pm

Much smoother withe the NGK plug

Ducati Scotty · **Reply #45 on:** July 09, 2012, 05:46:53 pm

Quote from: Lwt Big Cheese on April 27, 2012, 08:51:18 am

You have to modify until it becomes unreliable then bitch about the un-reliablity!!!

If it jams, force it. If it breaks, well, it needed to be replaced anyway

bikerboo · **Reply #46 on:** July 10, 2012, 07:46:16 pm

Hello,just for the record,have binned the Bosch and put in the NGK bpr6es as recommended by the guys on this forum.Stan is running sweet,short or long trips so we are both happy.X

meganuke · **Reply #47 on:** July 12, 2012, 01:39:41 am

I swapped out my plug tonight. It had a BR8ES in it. I noticed it seemed to lose a bit of power on the ride home today, struggling up some of the slight hills. It still ran smoothly and idled fine. I put in the BPR6ES. I'll report back after tomorrow's commute.

meganuke · **Reply #48 on:** July 12, 2012, 05:25:37 pm

I'm happy to report that the power has been restored with the plug change. The bike does run smoother, too. I noticed that I could actually see things in my mirrors at 65 mph. The throttle response is greatly improved. Transitioning from off-throttle to on used to have a delay of 1-2 seconds before acceleration would begin. It's always been there, so I thought it was just part of the bike's nature or due to the simple EFI mapping. Not any more! Throttle response is greatly improved, and it now transitions as fast or faster than every other bike I've ridden.

dynamyt · **Reply #49 on:** July 24, 2012, 02:59:31 am

Quote from: Ducati Scotty on July 09, 2012, 05:46:53 pm

If it jams, force it. If it breaks, well, it needed to be replaced anyway

"If it doesn't fit, get a bigger hammer"

"Square peg in a round hole, no problem. Oh, you meant it had to STAY square."

BRADEY · **Reply #50 on:** July 24, 2012, 03:49:08 am

Quote from: dynamyt on July 24, 2012, 02:59:31 am

"If it doesn't fit, get a bigger hammer"
"Square peg in a round hole, no problem. Oh, you meant it had to STAY square."

MEGANUKE

can you put a picture of your BPR8ES for reference purpose. Cheers. R

JezzC · **Reply #51 on:** February 14, 2020, 08:24:19 am

I know it is resurrecting an ancient thread ...
Since getting my 500 C5 last year I have been avidly reading all the great info on this forum. When I got my bike I serviced it and replaced the spark plug with another Bosch twin electrode. I haven't had any problems with this plug but reading this thread recently I thought I would get an NGK BPR6ES and see how the bike likes it.
It is winter here in the UK and I found that with the NGK until the bike really warmed up it ran awfully, spluttering and stalling. I can only guess that the twin electrode somehow performs better in cold conditions when the engine hasn't warmed up? I refitted the bosch and my problems went away. I have since out of curiosity fitted an NGK iridium plug and the engine ticks over and runs as well as the bosch and maybe better.
Anyway, hopefully my experience my be useful to any new UCE owners.

Ove · **Reply #52 on:** February 15, 2020, 09:01:38 am

What is the NGK code for that plug and did you adjust the gap?

JezzC · **Reply #53 on:** February 15, 2020, 09:07:17 am

Quote from: Ove on February 15, 2020, 09:01:38 am

What is the NGK code for that plug and did you adjust the gap?

The plug was a BPR6ES and I set the gap to 0.7mm

Ove · **Reply #54 on:** February 15, 2020, 10:16:27 am

Sorry, I meant the iridium plug

JezzC · **Reply #55 on:** February 15, 2020, 11:13:43 am

Quote from: Ove on February 15, 2020, 10:16:27 am

Sorry, I meant the iridium plug

The iridium is an NGK BPR6EIX and the gap is left as it comes

Ove · **Reply #56 on:** February 15, 2020, 12:06:21 pm

Thanks

gashousegorilla · **Reply #57 on:** February 15, 2020, 11:58:00 pm

When my motor was stock , I never had a problem with the stock Bosch plug either. I think a BPR6ES is fine, but a BPR5ES is better IMHO... the electrode will stay cleaner in cool weather when the fuel is harder to vaporize. It will stay cleaner and less prone to fouling . Autolite 63 is a good plug as well.

A good read....

https://www.dragzine.com/tech-stories/ignition-electronics-efi/the-great-spark-plug-debate-separating-fact-from-opinion/

JezzC · **Reply #58 on:** February 16, 2020, 08:12:28 am

Thanks for the link, an interesting read.
At least with only one plug it isn't much of an outlay upgrading a bullet to iridium

Boxerman · **Reply #59 on:** February 16, 2020, 03:08:11 pm

Quote from: JezzC on February 16, 2020, 08:12:28 am

At least with only one plug it isn't much of an outlay upgrading a bullet to iridium

Lets face it, an iridium plug on a standard Bullet is an expensive solution looking for a problem. Mine runs just fine on the standard Bosch.

Frank

JezzC · **Reply #60 on:** February 16, 2020, 03:49:24 pm

Quote from: Boxerman on February 16, 2020, 03:08:11 pm

Lets face it, an iridium plug on a standard Bullet is an expensive solution looking for a problem. Mine runs just fine on the standard Bosch.

Frank

Haha, I agree and I only strayed from the Bosch in the first place because curiosity got the better of me after reading this thread