Engine Update....Plus Question ref Spark Plugs

Ok, after lots of help from peeps on here (and plenty of swearing and throwing things around in my garage here is as far as I am. After stripping the engine down to the block and removing the pistons it was obvious I needed new rings and, at the very least, the cylinders would need honing. I approached a bike shop who said he could do it for £30 and measure the pistons and cylinders. I also priced up new sets of rings from yamaha dealer, £39.50 each pot. So thats £158 for the rings and £30 for the bike shop, £188 ($380). I managed to pick up a running xj650g maxim engine for £225 ($455) (including the Alternator, starter motor and both coils.) All the tollerances on the electrics are spot on the money and the engine has no leaks evident. So that is half way in the trike now. Plus I have a nice winter project of rebuilding the other engine (when funds and wife permits!) :lol:

The question ref spark plugs......I've always used BP7ES as stated in the manual, this replacement engine is already fitted with BPR7ES, what is the "R" for and what is the difference if any? I am going to renew the plugs, but just wondered what the difference was.

Cheers
Lea

 

R just means they're resistor plugs to reduce electrical noise. Not really required, but doesn't really hurt either.

Occasionally - and it's pretty rare - the extra resistance can cause some spark issues with the original coils. But if you're is running fine with them, no big reason to bother changing them.

 

I believe the R is for resistor plugs. Should work fine.

 

The R is for resistor. Many shops sell the resistor plugs because they reduce the EMI signature when bikes have radios. It also weakens the spark. So if you don't have a radio then I would switch the plugs.

 

You can go to NGKs website for a part number breakout chart that tells you all the details of each character/letter.

 

Finding plugs that DON'T have the "R" is tough at some Parts Stores.

They don't stock the "Non-sellers."

Since the Resistor Plugs make life easy for Cagers with Bose Systems and a host of electronic goodies ... the Resistor Plugs are the Manufacturers Recommendation for Cages and the Farmers have it just as good in the rigs they all drive bringing-in crops.

Speed Shops are a good bet if you want to lose the "R" -- !

 

Thanks guys, I'll give it a try with those plugs in, when I finish tidying up the wiring after the PO cut through the wiring loom/harness and extended it with 14" of yellow wire (yes! all the wires are correct colour going into the black bound tape, then at the other end.........ALL YELLOW!!!! AARRRGGHH!) I suppose thats the problem with having a 10' 1" vehicle!!!

And you all thought you had problems with the old fuse boxes! :lol:

Thanks again
Lea