[i7of9]

Hi All!

Well, I've finally decided that the gearing is just to tall on the S4 for the city. Since I use my duc ever day to and from work and I live in the city and work in the city, my clutch gets city type use and getting a clean launch has gotten progressively more difficult rather then easier (read: clutch rub problems). So, since I don't plan on doing 140 in 5th I guess I can give up a little top end to get a better launch! Suggestions? Experiences? Chain issues? Other gotcha's?

Thanks,

Borg Girl

 

[Speeddog]

Borg girl,
S4strati went down to a 14 on the front, and I think up to a 39 on the rear. He's in Burlington,MA. Made some comments about it being difficult to keep the front wheel on the ground until he got used to it.....

There have been some folks who comment on accelerated chain pad wear. Probably depends more on lubing, cleaning, suspension preload and pushrod length.

I've got no FHE on this, I regularly travel long distances on the freeway at 80-85, so lower gearing's not on my menu. I can see how I'd feel different if I was in SF...

 

[MarkV]

order either a 39t rear or a 14t front sprocket... it'll do what you're looking for. doing both would be the equivalent of adding almost five teeth to the rear alone... and that translates to a lot more frequent gear shifting. my thinking is ideally you'd like to keep the shifting down to a minimum but get a better launch but you don't really need a stump puller. either of those sprocket swaps by themselves will allow you to keep the stock chain unless you'd just want to swap it out for a lighter one. i'm more of a rear sprocket proponent, going larger rear has less overall impacts than a smaller front.

another thought since you've already got an after market slave for more leverage maybe try using stiffer clutch springs that will help reduce the rubbing at take off.

 

[Speeddog]

Borg Girl,
I was going to ask in my last post, but I forgot.

Can you describe the symptoms or behavior of clutch rub?

 

[i7of9]

Hi SpeedDog

Here is a good description of the problem:

http://www.ducatimonster.org/cgi-bi...=tech;action=display;num=1061522228;start=4#4

I do a lot of stop and go and hill starts in the city so my clutch gets lots of use. I am pretty carefull though and, until the rub started, I had 'reasonable' launches without over reving etc. With the rub I find that the clutch slips a bit during engagment causing the engine to rev more then I want which I am sure is just making the problem worse. Once fully released the clutch is fine, no slipping (yup, I have done accidental power wheelies and there is no problem in any other gear as there is no reason to have a lot of splippage except getting started in first.

I did take the clutch cover off and blew out the clutch dust. There was not a lot of dust. I also started the engine and disengaged the clutch while blowing preasureized air betweent the plates. This helped for a short while but the rub returned. My guess is that I have developed a glaze on the clutch plates.

So, I thought that with a shorter gear ratio my slippage during launch should be less and, after deglazing, my problem should go away and stay away [smiley=undecided.gif]

Borg Girl

 

[Speeddog]

OK, I've got it now.

It does sound like the plates are glazed a little.
When you open the clutch up to scuff the plates, check to make sure you don't have any warped plates.

Be gentle tightening the screws that hold the springs. I haven't had mine off, but several folks here have snapped screws by inadvertently overtightening them. They're pretty small.

It's not completely applicable, but I had a racebike with_really_tall gearing, had to slip the clutch in first gear until the bike was going about 60mph. I had some Barnett kevlar-faced friction plates, and they were bulletproof. It was a wet clutch, but I barbecued a set of the regular Barnett plates, but then had no problems with the kevlar ones and they always looked brand new.

Y'know, I'm going to take a look at my clutch. It has seemed a little "slippy" on takeoff lately. I've got a little over 5000 miles on it. How many miles are you at?

 

[penadamaz]

Drop a tooth on the front sprocket!
It makes the S4 easier in stop and go traffic.

It also makes it quicker. It will give you a bigger grin from 0-60 which is the world most of us live in!