Enker spark plugs

[balky1]

Time has come to change the plugs since old ones started to give me trouble. Instead of NGKs, this time I decided to experiment with a 'local' brand. Bosna Super or Enker are well known plugs in Croatia and surrounding countries. I contacted the factory to check which plug they recommend and they said that TWE85CPR are direct replacements for NGK DPR8EA 9. I ordered a set and when they arrived I noticed they are 1.5-2 mm longer than NGK. Do you think this is a problem. Look at the picture. I must say that gaps on these two plugs is not set to 1 mm so I believe that the total difference between the two would be around 1 mm. Thread length is the same like NGK.

[FJ_Hooligan]

Bring a piston up to TDC and drop something in the cylinder to measure the clearance then compare that value to the new plug reach.

Or, wait for Randy to respond.  :-)

[racerrad8]

Time has come to change the plugs since old ones started to give me trouble. Instead of NGKs, this time I decided to experiment with a 'local' brand. Bosna Super or Enker are well known plugs in Croatia and surrounding countries. I contacted the factory to check which plug they recommend and they said that TWE85CPR are direct replacements for NGK DPR8EA 9.

I went to the Bosna website and their information is very limited. I used a online sparkplug cross reference that popped up after googling Bosna.

Using the NGK number, Bosna does not have any cross reference for the NGK plug: http://www.sparkplug-crossreference.com/convert/NGK_PN/DP8EA9
When I enter the Bonsa number, I get this: http://www.sparkplug-crossreference.com/convert/bosna/TWE85CPR

Obviously Bonsa/Enker has not provided their information to this website, but I also cannot find a cross reference on the Bosna site: http://www.enker.ba/en/svjecice.html

So, back to the question at hand.

I ordered a set and when they arrived I noticed they are 1.5-2 mm longer than NGK. Do you think this is a problem.

I must say that gaps on these two plugs is not set to 1 mm so I believe that the total difference between the two would be around 1 mm. Thread length is the same like NGK.

The plug you have received is a much hotter plug than the NGK you are removing. When the electrode and porcelain insulator nose are longer, it takes longer for the heat to travel up to the base of the spark plug and dissipate into the cylinder head.

As you can see here, the longer porcelain and electrode on the left will run hotter than the recommended Yamaha heat range



As far as internal clearance, I believe you will be okay. But if it was me, I would remove the gasket and install the spark plug by hand until it seats. I would then rotate the engine one full revolution by hand to see if...

1) It does not complete the full revolution because it is hitting the plug
or
2) If it does strike the ground electrode and close up the gap.

If neither of those occur, then internal clearance is probably not an issue. But then you still need to ask yourself if you want to run a hotter spark plug. That in itself could have detrimental results if it burns a piston.

Randy - RPM

[balky1]

Time has come to change the plugs since old ones started to give me trouble. Instead of NGKs, this time I decided to experiment with a 'local' brand. Bosna Super or Enker are well known plugs in Croatia and surrounding countries. I contacted the factory to check which plug they recommend and they said that TWE85CPR are direct replacements for NGK DPR8EA 9.

I went to the Bosna website and their information is very limited. I used a online sparkplug cross reference that popped up after googling Bosna.

Using the NGK number, Bosna does not have any cross reference for the NGK plug: http://www.sparkplug-crossreference.com/convert/NGK_PN/DP8EA9
When I enter the Bonsa number, I get this: http://www.sparkplug-crossreference.com/convert/bosna/TWE85CPR

Obviously Bonsa/Enker has not provided their information to this website, but I also cannot find a cross reference on the Bosna site: http://www.enker.ba/en/svjecice.html

So, back to the question at hand.

I ordered a set and when they arrived I noticed they are 1.5-2 mm longer than NGK. Do you think this is a problem.

I must say that gaps on these two plugs is not set to 1 mm so I believe that the total difference between the two would be around 1 mm. Thread length is the same like NGK.

The plug you have received is a much hotter plug than the NGK you are removing. When the electrode and porcelain insulator nose are longer, it takes longer for the heat to travel up to the base of the spark plug and dissipate into the cylinder head.

As you can see here, the longer porcelain and electrode on the left will run hotter than the recommended Yamaha heat range



As far as internal clearance, I believe you will be okay. But if it was me, I would remove the gasket and install the spark plug by hand until it seats. I would then rotate the engine one full revolution by hand to see if...

1) It does not complete the full revolution because it is hitting the plug
or
2) If it does strike the ground electrode and close up the gap.

If neither of those occur, then internal clearance is probably not an issue. But then you still need to ask yourself if you want to run a hotter spark plug. That in itself could have detrimental results if it burns a piston.

Randy - RPM

Yep, their info online is terrible. I had to send an e-mail to get this information.
I also thought it is hotter because of the longer insulator. I just don't know why the guy would say it is a replacement for the listed NGK... I'll need to think about this.

[racerrad8]

Balky,

One more thing; Does the top unscrew off to leave the threaded stud?

If not they will not work with the Yamaha spark plug boots.

Randy - RPM

[balky1]

Balky,

One more thing; Does the top unscrew off to leave the threaded stud?

If not they will not work with the Yamaha spark plug boots.

Randy - RPM

It does.

[balky1]

I've contacted the factory once more and this is the explanation I've got (my translation from Croatian): "NGK DPR8EA 9 matches Enker TWE85CPR (gap 0.9 mm). We and NGK have almost the same heat values. Difference between NGK and Enker is in the size of the wrench (NGK - 18mm, Enker 16mm)."

I'll put them in and report on the behavior so that everyone knows.
The reason I've decided to try a different brand is the 'problems' I've got with the last NGKs I've put in. They started dying (they did do 15000 kilometers so it is probably the time). Nevertheless I think these newer plugs aren't the same quality like the old ones. I still have the factory installed ones (at least I think - that's the one in picture above) that work perfectly.
We'll see.
I guess I'm just bored.