Triumphrat

sussurf · 11-09-2012, 08:55 PM

I think I was averaging between 5.1-5.6 L/100km.
Correct me if I'm wrong but is that around or more than 50mpg?
When we dyno tuned the bike and after finishing the final mapping adjustments, I quickly threw on my modded exhaust and got the following (see attached image). The boat anchor is the run on the modded stock exhaust. Interesting hey? But I love the look and sound of the Tridents....Weight difference in about 2.2 kgs all up.
I'm sure you'll do well Phillip. Just take your time and take a little off at a time. After the TB's and the exhaust, consider carefully the head and cams. This is where I believe any more gold lies. The factory shaped throats on the inlet side were very ordinary. There just wasn't enough material to fit a nice curved throat in there right at the valve. I reshaped as best I could but they really needed to be built up & re-shaped on the roof of the downturned section. So mine were not great but I think I managed to improve on the ex-factory shaping. I'd love to see a Daytona head.
And cams are an option also. Sacrifice some of that massive low down torque to get some more top end HP.

pmc847 · 11-10-2012, 12:38 PM

Phil,

1liter = .264 gal
1km = .621 miles
5.3L = 1.399 gal
So, 62/1.399=44.3 mpg

I would be happy with that.

As for the boat anchor, very interesting results. That will be my direction for now. I'm on a tight budget, now that I am retired, and promised Jane I would not go overboard.

I did promise her a new seat for her comfort and an Ohlins or Penske shock for sure. The forks have been upgraded with different springs and valves shimmed. I have a fork braced ordered
http://i1237.photobucket.com/albums/...r/zrxbrace.jpg

http://i1237.photobucket.com/albums/...r/DSCN2992.jpg

Looks like my idea for air box intake will be feasible. It should open up the tiny intake hole to about 4.75" x 2.5". My friend might not get to that until later this winter. Hunting season is in the way right now.
Will keep posted with pics as things progress.

Cheers to you and yours

Philip

DaveM · 11-10-2012, 02:54 PM

Hi Phillip I am on my iPhone app so cannot see where you are from but I am guessing the USA so you are talking about US gallons not imperial?

Sent from my iPhone using Motorcycle.com App

pmc847 · 11-10-2012, 05:41 PM

I'm in the Madison, Wisconsin area. Yes, US gallons.

Cheers.

Philip

DaveM · 11-10-2012, 10:21 PM

Thanks for clarifying Phillip, I am easily confused at times!

jsprinter · 11-11-2012, 01:11 PM

Hi Phil. You mention that you believe it was the the head work that made the difference. I have about 55000 miles on my 03 955. One of the intake valves is showing close to lowere limit. If it indicates the minimum (0.1 m) this winter I will probably reshim. But, thinking down the road, I might consider doing the head. Sounds like you had a successful experience here. Who did the work and what was the cost? Any other advice. Also, when considering such a project I need to consider the rest of the engine. Did you in any way check to see if there was any bottom end attention needed (other than the transmission work you described). I love my bike and have taken care of it but at some point the law of diminishing returns kicks in and it makes more sense to replace the bike. Thanks for your instructive post. Obviously you have no fear of trying stuff and getting in there up to your elbows. You are a true road warrior. - Jim

sussurf · 11-12-2012, 04:03 PM

Thanks Jim.

I don't think the head work made the most HP difference. I suspect it was the TB and exhaust matching work, reinforced by the dyno session. The headwork, as it turned out, was a good idea despite the bike performing very well. I had overheated the bike and it seemed at least a couple of the exhaust valves were not seating correctly.

My advice was that the re-seating of all the valves using a CNC 3-way grind would give a great result in terms of the torque and rideability of the bike, so I guess torque more than anything. Mention was also made of long term reliabilty and fuel efficiency. It was also a chance to inspect all the valves and seals, a couple of which (seals) had to be replaced. I took the opportunity to do some DIY port work. I cleaned up as much of the poor casting marks as I could, and some of it on the exhaust side was pretty bad. I've already mentioned the intake throats but I guess that's mass production for you.

The work was done by a specialist cylinder head guy here in Sydney so I guess that's irrelevent to you. The machining, including refacing the head was about $350 and my mechanic charged me about $400 to strip and reassemble the head and re-shim everytyhing. I did, however, have to re-shim again slightly after torquing the head back on the motor so would probably save the shimming until the end. Just make sure to measure all the shims with a micrometer to check them and have quite a few spare sizes on hand. I made up an excel spreadsheet which really helped me figure out what shims I had and what I needed. Often you can shuffle them around limiting what you have to buy/swap for this job. I'm happy to share it with anyone who wants it just PM me.

I got to have a good look at both the top end and bottom end of the engine. The top end looked brand new. The bottom, ie the crankshaft bearing shells had some minor wear marks but certainly nothing to worry about. I'm expecting this engine will last a long time with reasonablr care. I was advised to try to ascertain which bearings were in there should I ever need to replace them but there were no discerning marks on them at all so I'm not sure how the process would work if you ever needed to order replacements from Triumph.

I know I could probably have thrown all that money at a new bike but I love this bike. It fits me, I love the way it goes, handles, sounds. I now have the bike I love optimized to be as good as it can be. And if I wore it out, I'd re-build it or do it to another one. I now have so much familiarity with these bikes, including the special tools so, I guess, I'm invested. I think it's a good way to be.