Trying to fix broken shifter spring

[Lucky Phil]

Well I finally got round to doing my gearbox shifter upgrade and took the bike for a run this morning.

I'm a pretty hard marker with these things and dont believe in talking up something that doesnt work even if it has cost me money.

The kit comes with a new cover ( with additional eccentric adjuster), shifter fork, return spring a banana plate and replacement detent arm pivot and no selector shaft seal.

Its a fairly easy task to transfer all the original parts that are going to stay to the new cover.

As the photos show the new accentric seems to be there to limit the shifter fork assy from too much sideways movement. The original cover had a non adjustable roll pin for this purpose that gave about 1.5mm clearance to the arm.

I set the accentric to give about 0.2mm clearance to the arm at a minimum during shifting.

The main accentric was also adjusted of course so that in 2nd gear and upwards selections the shifter fork hooks were centered on the drum pins.

So whats it like? is it worth the trouble and cost ( kit cost is $125us) Remember my bike is a 2000 model and I believe the 2003 and later bikes already have this system as std.

Having said all that its a definite improvement. Shifting is more precise and solid, shifting with or without the clutch ( I usually up shift from 2nd gear on without using the clutch) probably as good as my Ducati's now. 

So its for each person to consider the worth I guess.

 

 

Ciao

[docc]

What an excellent upgrade for the early bikes! L/Phil - how many miles/km on your Sport?

[LowRyter]

photos?  

[JBBenson]

Lucky Phil: Where does this upgrade kit come from? 

[Lucky Phil]

photos?  

Tried uploading by various methods from photobucket by the forum wont allow? If someone can  help I have photos which demonstrate the differences

Ciao

[Lucky Phil]

Lucky Phil: Where does this upgrade kit come from? 

Its a factory guzzi part/kit, p/n 973260900017.

Bought mine from Harpers Moto Guzzi

 

 

 

Ciao

[Lucky Phil]

What an excellent upgrade for the early bikes! L/Phil - how many miles/km on your Sport?

40,000klms, its shifting was acceptable but not brilliant, and the lever used to stick for a fraction of a second on completing an  upshift occasionally. I had replaced the return spring previously.

BTW I refilled the trans with the same oil which was only 1500klms old so new oil wasnt a factor.

 

Ciao 

[LowRyter]

Phil, you're saying this kit will prevent breakage of the pawl spring?  And that Guzzi installed them on models from '03 and later?

 

I thought the later bikes were the ones most vulnerable to this (like the Corsa Nero)?

[Zooter]

Just when you think the water is safe. I thought the mod kit was about upgrading reliable shiftability. At least the kit "should" contain matching spring and pawl, so reducing incidence of spring failure, one would assume. Am I actually better off getting a new spring and filing my original pawl for a snug fit?

[Lucky Phil]

You know I didnt actually check the diameter of the shifter fork boss when I got the kit,probably should have I guess. I worked on the assumption that if Guzzi was producing an upgrade kit with a new shifter fork assy included then it would be the type with the reduced boss dia.

The major changes seem to be the addition of an accentric and the banana link connecting the 2 gear wheel shafts. I dont really know why they even included the new shifter fork assy as it seemed to be no different to the original one in my bike which had the smaller dia boss. I just assumed that they included the latest reduced dia boss shifter fork assy as a precaution in case you had the faulty type.

From my understanding the larger dia boss on the shifter fork that causes spring breakage was due to a manufacturing defect. ie a bad batch, not a design problem. Thats why  the earlier bikes didnt suffer.

Ciao 

[LowRyter]

me too

[Zooter]

I am intrigued by the 90° spring fix in the other thread I bumped earlier. With the right spring, properly fixed to the pawl? and nyloc nut! holding down the other end attached to what? Seems to have held up for 3 years, better odds than chucking a correct spring on a correct pawl, but waiting on the guy who posted it.

[Zooter]

http://www.v11lemans.com/forums/index.php?showtopic=16930&page=2I messaged the guy who got the magic fix, he is a current member, beggars belief that he wouldn't bump his mechanic's fix, that went 500 miles, at every opportunity, maybe it failed, but it sure looks feasible regardless.

[JBBenson]

Just when you think the water is safe. I thought the mod kit was about upgrading reliable shiftability. At least the kit "should" contain matching spring and pawl, so reducing incidence of spring failure, one would assume. Am I actually better off getting a new spring and filing my original pawl for a snug fit?

 

Not snug fit, but loose. The spring shouldn't bind when flexed. When you have the cover in your hand, you will see what I mean.

 

If your boss is the larger 16mm, you can grind it down. I used a Dremel to get mine just shy of 15mm. Used a grinding stone to get it down and a polishing wheel to smooth it up.

 

I still carry a spare spring. Having changed it once, it is pretty easy, and could be done roadside if necessary, as long as you have the right tools, the most important one being a 5mm "stubby" allen.

[Zooter]

Snug at the wrap point of the small hook end, wherever that is, pawl or shift lever?

 

Could be academic if we determine a best bedspring to bodge at 90°. It looks like the pawl was drilled and tapped for a screw, loctite? The nyloc nut on the other end is a mystery to me.