Triumphrat

beachball6 · 06-02-2009, 10:56 PM

After much searching I have decided I am going to get the 15 and 47 or 49 sprocket set to replace my stock set (yea 14/42). I just need to know the proper chain length to get, or if I can use the OEM one (doubtful).

Also between the 47 and 49 rear, is there really that much of a difference? I mainly commute on my bike but romp on it during the weekend, and want a little more get up so when my other friends get on it I don't have to worry so much about clicking down multiple gears. I don't race the bike and don't care about top speed, with in reason.

Also I am a little anxious about the front tire being a little too happy, I understand it is all controlled by throttle but I have only gotten the front up a few times, and its not very fun for me. Can anyone make me feel better about this

Thanks
Shawn

01-TT600-w/can and tune.

GTiPilot · 06-03-2009, 12:43 AM

Amazing. I was just looking into the threads about changing sprocket size. As far as I'm aware my 01 TT is bone stock. The rear sprocket is stamped 42 which makes me assume the front is still 14. I think my bike is running great, but I've never owned anything other than dirtbikes and enduros.

What is the benefit of running a 15/47 or 15/49 setup? I think I read it in the technical sticky that changing the front from 14 to 15 helps with premature wear on the rubbing strip guide.

Could somebody dumb it down for me? Increasing the teeth increases the diameter and possibly allows for more torque to the rear wheel if you increase the ratio. The 14/42 early TT stock setup is a 3:1 and the later TT and S4 stock setup 15/45 is still 3:1. A 15/47 or 15/49 would be 3.13:1 or 3.27:1 if I am reading correctly.

When should a guy change sprockets and chain? I've got close to 17K now on all origal OEM parts.

Another dumb question. I assume that sprockets come in different thicknesses, to go with the accompanying different thickness of chains?

The change from the 525 to a 520 chain makes sense to me though. Less weight should equal less force to move it/stop it equating to faster accelerating/decelerating. Perhaps even a longer lifespan for drivetrain parts as well.

beachball, sorry for intruding.

stretchymantis · 06-03-2009, 05:44 AM

2001 Triumph TT600

My questions are almost identical to the two previous posts. I hope someone knowledgeable can provide some insight for us

. There are two things I have to add:

1) My front sprocket is stamped with 12T, although it seems everybody else's are 14. I thought mine was stock, but now I'm not so sure. Did they change the size during this year?

2) A friend told me to go down in size on the front sprocket and up in the rear in order to gain torque, but I keep seeing posts that go up on both sprockets. After reading GTiPilot's post, I'm wondering if it's because of the rubbing strip guide that you shouldn't go down in sprocket size for the front?

Thanks so much!

GNTurbo6 · 06-03-2009, 02:16 PM

Stock is either 14/42 or 15/45 depending on year. I recently did a 520 conversion and went to 15/47. I read that this gives a little more torque and some how even increases top speed? I may pick up a 14t front sprocket so I can swap things out quickly and that would pretty much be the same as the standard -1/+2 that people do. With my setup, I cut the 120 link chain down to 108. It goes pretty close to the tightest that the adjusters allow so with 15/49 you may need to go with 110 links. When I tried 110 I was worried that I would run out of adjustment space and I didn't want to have to get an extra rivet type master link for when I had to cut 2 more links out.

yimmit · 06-03-2009, 04:29 PM

here's a website where you can work out what difference gearing changes will make to your bike
http://www.gearingcommander.com/

beachball6 · 06-04-2009, 10:00 PM

I did some more googling and found this site http://www.cartestsoftware.com/fz1/4...tallation.html looks like it is a sprocket install for a speed 4. The guy said a 47 tooth should fit with some room to spare if you put the sprocket/chain on as you pick up the swing arm. I'm hoping there is room for a 49 also, as my chain is ~4k old.

I just ordered vortex 15F and 49R sprockets, I hope I can tolerate the revs and my front keeps its relationship with the ground.

G/L to all, I'l post up my impressions and issues as they arise.
Thanks!
Shawn

beachball6 · 07-08-2009, 07:40 PM

Facts:
-stock chain will NOT fit
-The bike feel much much more peppy, and passing in 6th is easy
-You'll need a 116 tooth chain
-The front end keeps its relationship with the ground but can easily be picked up, if I try. Same w/ 2nd gear at the right rpms throttle off then on and you get the tire off the ground a little.
-Highway revs are definately higher usually its about 500 rpms less that your speed. (at 60 in 6th you'll be at ~5500, 85 is roughly 8000)
-No way you can fit the rear sprocket under the chain gaurd it must be lifted/spaced out from the trailing arm.

Hope I help some people, if there are any other questions post them up.
Shawn

Will · 07-09-2009, 11:27 AM

It sounds like the chain length question has been answered. I always used 110 links because I went back and forth between 15/47 and 15/49 on a fairly regular basis. The reason for a bigger front sprocket is to reduce wear on the strip on the swingarm, but it also makes your chain last a little longer because the bend isn't as sharp. Lowering the gearing as a 47 or 49 tooth rear sprocket does, even with a 15t front, improves both acceleration and top speed. Top speed is limited by wind resistance and the amount of power the motor has to overcome the resistance. The gearing change puts the motor into a better part of the power band. I didn't expect it when I first changed the gearing on my TT600 when I had one, but it was quicker and faster. The faster top end is just a bonus, but you won't need it unless you are on the track.

The last thing is regarding chain length. A chain doesn't really stretch. What happens is the rollers start to wear, and when they do, they wear inside the side plates. Shortening a worn chain means you just have a shorter, worn chain. It goes into it's death stretch, and you will be adjusting it every 300 miles or so whether you shorten it more or not. 110 is fine, and you don't run out of adjustment until the chain is toast anyway.