PDA

View Full Version : Sprockets



Rev
08-12-2004, 05:59 PM
I'm thinking about changing my front sprocket on my 748 to give it a little more "pep". :happy44:
From what I've gotten from other conversations is to up the stock 14-tooth front sprocket to a 15.
Does anyone out there have any experience or thoughts on this?
Has anyone actually changed sprockets? (front or back) and what were the results ?
Also, who makes good sprockets?

Bong
08-12-2004, 06:17 PM
From my recollection, your 748 should have 14/38 gearing as stock. I wouldn't recommend changing the front, maybe go up to teeth in the back to 40. If you get a quick change kit, make sure you get the one that prevents the bushings from backing out. AFAM makes one that has this feature, I'm sure Jon at Duc Sea can help you out. Good luck.

Holeshot
08-12-2004, 07:36 PM
If you're looking for more pep you can either drop the front 1 tooth (not at all recommented even a 14T is pretty small) or go up a few on the rear sproket.

I spent a little while at DNW2004 talking to a few people (my chain/sproket are SHOT) and the consensus add 3 teeth to the rear sproket. You'll need a new chain to do this. On other bikes I've gone 2 teeth and just loved it (first time I did it though it was on my F2 and I went 42->40. DOH, I geared it up, poor thing could barely get my lard-arse off the line! :happy57:

So when I do my chain and sprokets it will be 15/39 and I'll see how I like that.

Bill Anderson
08-12-2004, 08:30 PM
I'm thinking about changing my front sprocket on my 748 to give it a little more "pep". :happy44:
From what I've gotten from other conversations is to up the stock 14-tooth front sprocket to a 15.
Does anyone out there have any experience or thoughts on this?
Has anyone actually changed sprockets? (front or back) and what were the results ?
Also, who makes good sprockets?

"Upping" the front sprocket to a 15 will give you less pep, not more. From what I have read, 14 is as low as you want to go in the front. As others have pointed out, your only choice is to start adding teeth to the rear spocket. I have been told that since your front sprocket has an even number of teeth, you wil want the rear one to have an odd number of teeth to minimize sprocket and chain wear.
Bill Anderson (02-ST4s) Edmonds, WA.

Rick Rinaldo
08-12-2004, 10:11 PM
Go to a 41 or 42 in the back. There will be a noticable difference and it will not affect your top-end too much. Also, take a look at getting lighter flywheel.

Rick...
WMRRA 123

triple9kyle
08-13-2004, 06:05 AM
Rev, I did the opposite thing (same end result, quicker responding), i put a larger sprocket on the rear of my old 2001 748. I would HIGHLY recommend this. I thought it changed my bike into a more responsive machine.
go for it.
Kyle.

darkduc
08-13-2004, 09:22 AM
I'm planning on going to a larger sprocket on my 749 as well. I'd do it now but I have a problem trading out the stock chain and sprocket for new ones when the OEM parts still have plenty of wear left in them.

I could have my mind changed though. How much of a difference does it make, performance wise?

Rev
08-13-2004, 10:44 AM
Thanks everyone for the good info...
Time to start shopping :D
And I'll let you all know what happens. :happy44:

MichaelN
08-15-2004, 11:01 AM
Rev,

I just changed my rear-sprocket on my '99 748 to a 41-tooth quick-change (w/ carrier as well) one by STM. The bike is definitely more "rev-ier" and more fun than it was stock. I put on a new front sprocket (+ new chain DID ERV2) as well but kept it at 14 teeth.

I ordered most of the parts form MotoWheels (since I was already ordering new wheels from them) and had Ducati Seattle install everything. I was originally just going to add a tooth or two (from 38 to 39 or 40), but the person I spoke to at MotoWheels said not to bother with anything less than 41 (he had a 748 as well).

Michael

Holeshot
10-28-2004, 02:14 PM
I've been poking around different sites and trying to figure out who I would order my sprockets, quick-change and chain from.

It was a close call between the AFAM kit from SprocketCetner and Ferraci (Ferraci was a bit more) untill I thought about checking Evo and behold they had a nicer-looking (better ?? ) Q-C make for them, AFAM parts for $308.00 shipped to WA. :happy44:

520 setup
15T front
39T rear

Hopefully the reduced weight from the 525 will be a little noticed but most of all the lowered gearing I'm hoping will add some more kick and make thost occasional stop-go traffic bouts a bit more managable.

I'll take pics when I get the parts in and start putting them on.

Holeshot
11-04-2004, 06:39 PM
OOOOOH. Parts just arrived. The 39T was on infinate back-order (DOH!) so I got a 40T instead. Yikes. Am I insane? Well, upside is that the rear is now an AFAM compatible quick-change unit made by Evoluzione AND the unit does have the rim on the back of the changer to prevent the cush-drive components from backing out (I guess this was a problem with early AFAM QC's)

Well, here is a pic of the stuff. Man.. finally. something fun to do tonight besides weave baskets.....

lindsay
11-05-2004, 12:46 AM
i changed the 14/36 stock gearing (on a 748R) to first a 14/39 and then a 14/41 (with an AFAM quick change just like holeshot's.) for SIR, the 39 was wrong (in-between gears on turns 4,5,7, and 10) but the 41 seemed perfect. was seeing 150+ through turn 1 so top end wasn't noticeably down. much better responsiveness and the gearing was well matched to SIR. haven't tried it on other tracks (or the road for that matter) though.

what about monsters? what are other folks running on a 900? it's time for a new chain and sprockets.

--
lindsay

CINDESMO
11-05-2004, 08:57 AM
I am running 15/41, which seems like a pleasant compromise for my bike which is a 2000 M900S. Since it is my commute bike I don't want it to be uncomfortable at 80mph. I also had a 40 for a while which I liked a lot, but then I realized that my bike had two more gears that I could use. :happy57:

Holeshot
11-06-2004, 09:18 AM
Almost done. Installation has been A LOT simpler than I had feared with the big nut on the left side. Impact tools are great. Not having the right size socket sucked. It's a 41mm and NOBODY had it within reasonable driving distance. Tacoma Screw (up here in Bremerton) did not have it either BUT they did have the SAE equiv of 1 5/8". I generally don't pull such hacks but on a nut of that size a tiny bit of play does not worry me much.

In the end the socket fit as well as my Snap-On 46mm does on the other nut so I went for it and had no problems.

2 things keeping me from testing this out.
- need to get a chain rivit tool (I should have that in my hands at 9 am)
- somehow lost the lock ring that goes on that left rear axle nut! DOH! How in the heck did that get lost!??!?! Of all the things to loose too... frick!!!!!

All I wanna do is zoom zoom zoom....

Having the quick-change will be nice. And the chain came in exactly the right legnth out of the box. No cutting required. I guess the extra 4 teeth on the back covered the typical extra links in new chanins.. ahahhaha

Now I'm off to go and search the garage again this morning. Maybe I was just too frustrated with myself to see it last night.. :)

Looks like Sunday will be a decent day for a ride.. hopefully I'm out doin' it!

Mental998
11-06-2004, 11:37 AM
If you have a Harbor Freight near you, go there. They have a set of huge metric sockets with a ratchet, two extensions and a breaker bar all for about $45.00

I think Snap-on whats that much for one socket.

Holeshot
11-06-2004, 03:35 PM
If you have a Harbor Freight near you, go there. They have a set of huge metric sockets with a ratchet, two extensions and a breaker bar all for about $45.00

I think Snap-on whats that much for one socket.

Yeap. $56 for my 46mm socket. OUCH. (did I mention ouch?).

BTW.. THX for the FW!!! Arrived Thursday with the sprocket stuff. WOO HOO!

Just test road the bike. That 40T really REALLY improved the streetability of the bike. Night and day! Downside is that my quick on-the-road math puts my ne top-end around 155~160 MPH. Not an issue on the street (for me) but on the track?? I might not be able to keep up on those long tracks (doesn't Spokane have some insanly long front straight, not that PIR without the festival curves is short either).

Too bad it was raining and I did not feel like whacking the throttle open to see how it jumps off the line... but I can get the clutch let all the way out before I clear the intersection which is new to me.. :)

weeeeeeeeeeeeeeeeeeeeeeeeeeeee weeeeeeeeeeeeeeeeeeeeeeeee

Best part is that I get to rivet the chain all over again some time next week.
:p Practice makes perfect, no?

Torben
11-06-2004, 11:05 PM
Nice, dude!
happy birthday btw :happy36: (ye old bastard :happy57: )

lll0228
11-07-2004, 12:57 AM
Happy Birthday Old man!

Chris Koxlien
11-07-2004, 09:37 AM
If you want a custom gearing recommendations. Have the gearing guru do a report for you. It is the best $29 you can spend to get some ideas about your current gearing verses a new ratio.

Well worth the money rather than doing trial and error.

Holeshot
11-08-2004, 08:59 AM
Nice, dude!
happy birthday btw :happy36: (ye old bastard :happy57: )


SSSSSHHHHH!!!!! You're harshing my denial!!!!
:happy57:

Holeshot
11-08-2004, 09:18 AM
Now that I have recovered from my birthday party (ouch) I did some figgerin..

Calculated some gearing factors and made the assumption that at 10,500 RPM the bike is capable of 178 MPH (read that somewhere - not at all sure if that's true).

Based on that..

At 10.5k rear wheel RPM calculation:
15/36 4375
15/40 3937

So if 4375 wheel PRM is 178 MPH then at 3937 RPM my ground speed should be a hair over 159 MPH. Granted there is a big assumption in there but the relative change is the same so.. it looks like my crude highway guess of 155~160 was pretty close (on the upper end anway - wind resistance not considered).

Geez.. I must be still feeling the afteraffects since it took me about 10 min. to recall my basic algebra and solve the equation! :eek:

Holeshot
11-09-2004, 12:18 PM
Some pictures from the install. Dang that rear sprocket looks dorky-big.. :p

Jim is Cool
11-09-2004, 03:46 PM
put it next to the 43 tooth sprocket I'm using on the ST.

At PR I'm still a bit tall, then again, it's trying to haul a bit of wieght, I get an Indicated 160 at T1, I figure since I'm leaned over that's even more optomistic than would be normal since your RPM's pick up a few hundred on due to smaller diameter. And an FYI, Ducati's speedo's are VERY optomistic once you get over triple digits.

I haven't used the gearing at Spokane, but it should be pretty close. Top speed is good, but at PR since it's technical, you want to out accelerate your opponent.

Mental998
11-09-2004, 05:04 PM
If you have a Harbor Freight near you, go there. They have a set of huge metric sockets with a ratchet, two extensions and a breaker bar all for about $45.00

That set is on sale right now... $34.99 19mm to 50mm

UKDuc
11-09-2004, 05:37 PM
That set is on sale right now... $34.99 19mm to 50mm

That is a frickin bargain by anyone's standards! Seems the nearest one is in Tacoma. Loads of other cool stuff on their website too...