Triumphrat

Sport · 08-19-2006

Just retrived my 02 Sprint ST from the dealer.

Come to find out my ECU was wacked out. It works fine, it just didn't know what an ST tune was. Bill, the mechanic flashed the system and installed a stock 2002 ST tune, but my bike still didn't like it. At the same time, he replaced the semi-new spark plugs with stock plugs but quickly realized the plugs that came out of my bike were not stock 2002 ST plugs; infact they were 2002 955i Daytona plugs. Stock 2002 ST plugs are larger diameter and coarser threads. A little investigation revealed that I have a Daytona head on my ST engine. I guess Bill worked the ECU to match a Daytona tune (or close to it) and it seems to be running much smoother now than even before my friend dropped it.

I'll get the cowlings repaired and painted hopefully this week and have a test ride soon.

Couple of questions:
1) Am I the only one with a big head :wink: or do most/all 2002 ST's have big heads?
2) Other than spark plug size, What differences are there in Daytona vs. St heads? Ports, valves and cams larger smaller...maybe timing?

Things that make you go Hmmmm.

[ This message was edited by: Sport on 2006-08-19 10:28 ]

frizbee_dog · 08-19-2006

The daytona is different largely due to the cam. You will definately have more HP than a stock ST.

[ This message was edited by: frizbee_dog on 2006-08-19 12:04 ]

Stlakid · 08-19-2006

My RS has the smaller plugs as well (10mm) They made a head change on the 2002 models and up. Knowing Triumph usually runs their parts out if you had a 2002 with the larger plugs it was probably one of the previous 2001 heads that got installed on an early 2002 bike. Just a guess though.

Sport · 08-19-2006

Quote:

On 2006-08-19 13:12, Stlakid wrote:
My RS has the smaller plugs as well (10mm) They made a head change on the 2002 models and up. Knowing Triumph usually runs their parts out if you had a 2002 with the larger plugs it was probably one of the previous 2001 heads that got installed on an early 2002 bike. Just a guess though.

Stlakid,

The dealer showed me the two plugs. My 2002 uses the smaller diameter plug (the same used for the S3 and the Daytona) while other ST's (earlier or later models I don't know) used a larger dia. plug.

Either way, If I have a head from a Daytona/S3, is it possible I have the cams from them as well or can the ST cams be swapped for the Daytona/S3 cams?

Stlakid · 08-20-2006

I was checking this a while ago and the cams are a swap providing the pistons have the clearance for the added lift. The valve springs are the same for Daytona or the Sprint so they would not need changing.

If you have a 2002 the head and cam would be the same in the Sprint, RS, or the Speed 3. The Daytona gets different cam, Pistons, Cylinder liners and shot peened rods for durability. Not really a lot of difference between them mechanically.

Obviously the tunes are quite different as well with the Daytona having a much higher red line. But I must admit my RS is still pulling hard when it SLAMS up against the rev limiter! I'm pretty sure the Sprint, RS, Speed 3 will rev higher, it's just limited for durability. I guess that's not really a bad thing, but it is a bit abrupt IMHO.

Sport · 08-20-2006

Stlakid,

Sooo,

If the 02 RS and ST's have an S3 head then ours maybe easier to modify for more power???

My 02 pulls very hard through the rev limiter as well. Anybody try lifting the limiter up 500rpm?

How about cams, has anybody checked valve/piston clearances to see if a Daytona cam could fit?

Just dreaming out loud :hammer:

Sport · 08-21-2006

Can I assume there are only a few of us aware of the 2002 model RS/ST's with Daytona/S3 engines?

Has anybody swapped cams or other engine parts?
What tunes seem to work best for a stock 2002 ST/RS?

This has got me curious...
:hammer:

Stlakid · 08-21-2006

I wouldn't do the change over unless you did all of it. To get the added power as the Daytona you will need to raise the redline as Triumph did on the Daytona to 11,300. (? I think thats the correct number)
The Daytona gets Forged Pistons and Shot peened rods both there to cope with the added power and RPM's. The cylinders also have aluminum coated liners instead of iron ones. The coated aluminum liners will dissapate heat faster and may have less friction than an iron liner, but I'm not sure that would really be a factor.

Personally, I love the WIDE power band of the RS, Sprint, and S-3 955i motors, but I must admit I have never tried a 955i Daytona myself.

GET A TURBO! :-) Expensive, but POWER EVERYWHERE! not just at the top end.

Turbo Sprint