15T Front Sprocket

Put my 15T on at the weekend and its made a hell of a lot of difference (for me!) Much smoother, easier to ride. I don't like jerky pickup, so the 15T makes it much more gentle, the gears feel in the right place now. Even managed to get into 6th gear!!!

If you haven't done it yet, do it, you'll love it

I started with the 15T front and then went to a two up sprocket for the back when I changed the chain. HELLOOOOOO NURSE!! Did THAT wake my baby up or what. No loss of top end as I tapped out in fifth. Now it makes it into sixth gear and the same speed. TOTALLY worth it and if you think it is fun with the 15T front, try the rear mod as we well. Running Map 2 as well and may have to core the pipes before the summer is over.

Ready to change.

Just recieved my 15 tooth front sprocket today ready to fix on the weekend and just wanted to no if its easy as described by a few?:crazy

After losening the main axle nut and then the adjuster bolts does the wheel slacken of enough to pop the chain over the front sprocket without any problems ready for the new 15 tooth sprocket?

Rather be pre-warned if there are to be any problems..:rolleyes

Thanks guy's:thumbup

mathand1 said:

Just recieved my 15 tooth front sprocket today ready to fix on the weekend and just wanted to no if its easy as described by a few?:crazy

After losening the main axle nut and then the adjuster bolts does the wheel slacken of enough to pop the chain over the front sprocket without any problems ready for the new 15 tooth sprocket?

Rather be pre-warned if there are to be any problems..:rolleyes

Thanks guy's:thumbup

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Basically mate yeah, that simple.

The only issue i guess could be getting the chain tension right again afterwrds.

Bring it down if you like late Sunday arvo and we can do it togetehr.

doc.heckle said:

Gen 1 stock 17/43
go to 15/43 and some fresh underwear !

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People try various combinations, One of the most common on the Tuoldo (Gen 1) is 16/44, which is pretty much the same as 15/42 etc.

There is a spreadsheet kicking about that does the gearing calc's for you if you care, there is a copy on AF1 in TechTips, I think I have a copy somewhere. (I see I can't upload an *.xls file, so you will have to upload it)

The reason that Aprilia ship the bikes with the tall gearing is to get them through the various emission regulations, this coupled with the very lean fueling at low regs on Map 1 of the ECU's.

The Dealers are supposed to sort all this at the first service, but many don't. when I picked my old bus back up from it's 600 mile service they hadn't de-restricted the intake, exhaust or cut the wire on the chip, all of this was done for me by the local tuners when I had the dyno work done a few months later.

Yes, Paul!

When I picked up my '07 new as a holdover model in Dec. '08, I noticed the gearing to be taller than my '03 and made a mental note to change it over at my first service. My sales rep asked how I liked the bike, and one comment was re: the gearing. He stated pretty much what you said about USA emission standards prompting the taller gearing and that, he believed that the dealership (Spectrum Motorsports) routinely changes over to a 15 tooth as they receive the bikes. Perhaps they overlooked mine, he thought.

Come the 600 mile first service, I wound up with the bill for a new sprocket and labor. I didn't realize until your post that I need to address fueling and restrictions in breathing other than the air box as well. Thanks for the overview. It will help me move on to what is next. --Jon

Jonnyallover said:

Yes, Paul!

When I picked up my '07 new as a holdover model in Dec. '08, I noticed the gearing to be taller than my '03 and made a mental note to change it over at my first service. My sales rep asked how I liked the bike, and one comment was re: the gearing. He stated pretty much what you said about USA emission standards prompting the taller gearing and that, he believed that the dealership (Spectrum Motorsports) routinely changes over to a 15 tooth as they receive the bikes. Perhaps they overlooked mine, he thought.

Come the 600 mile first service, I wound up with the bill for a new sprocket and labor. I didn't realize until your post that I need to address fueling and restrictions in breathing other than the air box as well. Thanks for the overview. It will help me move on to what is next. --Jon

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Jonny

The restrictions I refer to are on my 05 Gen 1 Tuoldo.
As far as I know the Gen 2 needs the gearing (sprocket) change, and as it is often sold in the UK with Akra cans needs the ECU swapping to Map 2 with an Axone by a dealer. I do not know of any restrictors in the airbox or exhaust on the Tunuo's. They have different ECU's etc from the Tuoldo's.

Good! Thanks for that clarification, Paul. I won't be looking for air intake restrictions, then.

You and Mogster particularly were a big help on a thread about basic fixes everyone should address first. For those following this thread, this advice can be found here.

I've had some crash repair issues, so most extra change has gone there, but I'm excited about the possibilities in clearing up the T's nasal passages and esophagus based upon the above and the referenced thread. Many thanks!