Triumphrat

9 miles from hinckley · 11-14-2009, 04:02 PM

what type of spark plugs should I be using in my 97 t'bird.the owners book says DPR9EA-9 triumph repair book says DPR8EA-9.It has mikuni carbs if that makes a difference.

Slinky · 11-14-2009, 04:59 PM

The parts book lists 8EA-9 as standard and 9EA-9 as a "winter" plug (i.e. one grade hotter). I never felt the need to run a hotter plug in winter- but I can't remember what is fitted in my bike.

9 miles from hinckley · 11-15-2009, 01:35 PM

Thanks for that slinky,mine came with 9's fitted but they seemed to foul.I changed to 8's but it seems worse.it may be that I need to look at the air filter /carbs.Iv'e got triumph off road silencers on at the minuite so it could be them.any other ideas?

Slinky · 11-15-2009, 01:56 PM

How many miles has the bike done? The airfilter seems like a good place to start.

Bear in mind that the Mikunis are notorious for wearing out quickly. The needle jets go oval in as little as 10k miles, and the plastic slides get badly worn.

It's a good idea if you plan on keeping the bike for a long time, to look for a set of Keihins.

ps you might want to check the jet sizes if you are going into the carbs.

9 miles from hinckley · 11-15-2009, 06:00 PM

The bike has done 8000 miles.I've got a k&n filter but Ithink I'll get the keihins as I really like the bike.do they make much difference to the performance?. thanks for all your help.

Slinky · 11-16-2009, 03:19 AM

No, I don't think they help performance, at least on as standard bike. The inlet rubbers on the Mikunis are restricted, in order to aid low rpm torque. The inlet rubbers on the Keihins are unrestricted.

In practise, this makes little difference. I switched to Keihin carbs but after much experimentation, I switched back to the restricted rubbers. The bike just seems to "spin up" quicker with them. For what it's worth, I have the "off road" mufflers too.

geebee · 11-20-2009, 09:46 PM

Concerning Hot/Cold Spark Plug ratings: the higher the number the colder the plug. Thus, an 8 is hotter than a 9. So if you wanted a hotter plug for winter use you would choose the 8 not the 9. In Hotter climes go with the 9, in colder go with an 8.

Slinky · 11-21-2009, 01:31 PM

Quote:

Originally Posted by geebee

Concerning Hot/Cold Spark Plug ratings: the higher the number the colder the plug. Thus, an 8 is hotter than a 9. So if you wanted a hotter plug for winter use you would choose the 8 not the 9. In Hotter climes go with the 9, in colder go with an 8.

True. My mistake, the book lists 9EA-9 as standard and 8EA-9 as a winter plug. Apologies for any confusion caused.

tnsen · 11-21-2009, 04:58 PM

ok...I had my96 bird for 4 years now...when i first had got it..I had a major problem with fouling.....i couldent go 100 miles without fouling...I switched to ea8 ....now she runs beautiful......offroad pipes...k&n airfilter....a dealer here in michigan, highly reccommended the hotter plug......just my 2 cents.....TOM

9 miles from hinckley · 11-21-2009, 05:59 PM

Thanks for all your help,I have put the 9's back in and it seems to run better.Did you have to rejet your carbs for the k&n filter and off road pipes.