Griso 1200 Kling Klang

[jihem]

Hi all,

 

I had more time and the (relative)* pleasure of riding more my 8.000 kms 2008 Griso 1200 4v around and I find the gearbox very noisy when engaging gears in, whenever the bike is moving or not.  Even when i go up or down a gear and I carefully and slowly engage the gear, it's more often than not annoyingly noisy and make a  strong metallic sound. When the gear is on, the gearbox  isn't noisy, it's really the moment when the gear is passing in that the noise occur.

 

Furthermore, the bike reacts strongly when first gear is engaged: the bike tends to jump forward when the gear is put in, more than with every bike i had previously. The clutch is fine, it's not like it slips, it's just like a strong reaction or else...

Common characteristics of the Griso 4V ?
Is there anything my mechanic could do to atenuate the noise and the nervous reaction ?

 

 

 

* : i'm not crazy about the Griso 1200: it's a very potent bike but I miss something more organic.

[pasrider]

I have a 2009 Stelvio 4V, and shifting from neutral to first gear (while stationary) can be noisy.  When the engine/transmission is cold, this is not an issue for me.  Any other time, here is what I do to lessen the noise:  when at a stop, I hold in the clutch lever 5-10 seconds, then slowly but firmly push the shift lever down to first gear -- this usually works well, to some extent.  When upshifting, I generally 1) preload the shift lever and then 2) quickly blip the clutch lever and shift -- this always works.  And, prior to downshifting, blipping the throttle to match engine revs with what the revs will become in the downshifted gear make for a quieter gearbox.

 

Hope this helps! 

[jihem]

Thanx.
I'll have the mechanic looking into changing the gearbox oil. What's the best oil for it ? Any special advice ?

[pasrider]

I use RedLine Shockproof Heavy in both the gearbox and final drive for the Stelvio, and did the same for my Cafe Sport.  Lotsa Guzzi-heads swear by it!

[DeBenGuzzi]

Redline shock proof heavy IN EVERY guzzi tranny plus bevel, it really works. I have the same issues with my griso 1100 except the lurching, I think it's just how the clutch and tranny are I have no slipping and the rest of the gears are fine but first gear at low speeds worries me a little almost like an elf is inside there with a hammer for a second, I'm not alarmed but curious what the hell...

[Paul Minnaert]

could be that clutch doesn't come free. air in clutchline, or the pushrod lenght.

 

You can make the griso better by mapping the ecu, with guzzidiag you can do that yourself, no costs!

[jihem]

Thanx all. Problem has been taken care of via the use of Redline !

[DeBenGuzzi]

I'm worried about my clutch, think its got to be the clutch, sounds like a midget in there with a hammer at low speeds when cold, doesn't seem to be there when hot so I have to wonder if it is something to do with the hydraulics and the clutch because it is setup to grab dang near the very end of the lever. also when cold shifting isn't as smooth, going into first I sometimes get a false nuetral. maybe I should have it looked over, or at least goto the local guzzi club meeting and let them kick the tires for some free advice. 

[pete roper]

Redline shock proof heavy IN EVERY guzzi tranny plus bevel, it really works. I have the same issues with my griso 1100 except the lurching, I think it's just how the clutch and tranny are I have no slipping and the rest of the gears are fine but first gear at low speeds worries me a little almost like an elf is inside there with a hammer for a second, I'm not alarmed but curious what the hell...

On your 1100 it may well be that the knocking is coming from the face cam shock absorber which on early models was in adequately sprung.

 

Pete

[DeBenGuzzi]

 

Redline shock proof heavy IN EVERY guzzi tranny plus bevel, it really works. I have the same issues with my griso 1100 except the lurching, I think it's just how the clutch and tranny are I have no slipping and the rest of the gears are fine but first gear at low speeds worries me a little almost like an elf is inside there with a hammer for a second, I'm not alarmed but curious what the hell...

On your 1100 it may well be that the knocking is coming from the face cam shock absorber which on early models was in adequately sprung.

 

Pete

 

I did a search and saw you addressed this before, your fairly thorough explanation with pictures means I get it and it's nothing to worry about (: Mine isn't too bad just real low speeds when not really under load like you describe. 

[commando tod]

I'm worried about my clutch, think its got to be the clutch, sounds like a midget in there with a hammer at low speeds when cold, doesn't seem to be there when hot so I have to wonder if it is something to do with the hydraulics and the clutch because it is setup to grab dang near the very end of the lever. also when cold shifting isn't as smooth, going into first I sometimes get a false nuetral. maybe I should have it looked over, or at least goto the local guzzi club meeting and let them kick the tires for some free advice. 

By the time its hot, the midget is too worn out to pick up the hammer. So drown the wee fella in Redline.

[DeBenGuzzi]

I changed it out to redline the day I brought her home the best stuff on earth 

[Wacholek]

Hi everyone,

I know that this is rather old topic, but it is still actual.

 

THE PROBLEM:

I have a Stelvio 4V with 15k miles on the clock. I have the same issue with the loud gearbox.

When engine is cold everything is perfect sooth. Up and down shifting, first gear from neutral at stand still jumps in without even a click.

Situation changes when engine gets hotter. Hotter->Louder.

First gear jumps in with a big bang and up and down shifting with the noticeable bang.

However clutch is not dragging. On central stand, engine running, clutch disengaged, first gear in, wheel is not spinning at idle.

 

THE INVESTIGATION

I've started from the clutch free play check, bled out the system, master cylinder check and lubrication of any necessary parts. I removed the secondary cylinder, pushrod. Lubricate as it was said in the manual.

Put it all back together and.... noting changed. So I've putt more effort to the clutch design. What I noticed is that this, single plate, clutch has a tendency to have very small drag. It can't be avoided in that kind of design. It is mostly related to vary small clutch play between engage and disengage position and construction of a central clutch spring.

Since the "abnormal" behaviour started to be noticed from around 2000 miles on the clock, after a numerous checks and after 6 oil changes I finally reach the conclusion, which agrees with the Guzzi service investigation.

 

THE CONCLUSION

This gearbox behave like that.

There is nothing to be done except to pick the right oil and learn how to ride.

I have to agree that Redline Hevy is much better than the Guzzi factory oil, but the best from all I've tested was 85W140 ENI ROTRA MP.

 

There is one simple explanation for the above mentioned problems, especially for the first gear bang. All this is because of the gearbox and clutch design.
After few k miles the gearbox is already broke-in, so it gets a little loose. I the same time it starting to work with a minimum internal friction.

Guzzi gearbox have 3 shafts (standard motorcycle gearbox have only 2). One is the main shaft connected to the clutch plate. It has a fixed sprocket which is connected to fixed sprocket on the second shaft. When it's on neutral no other sprocket are spinning. That limits the internal friction to only 3 bearing and 2 sprockets. The sprockets friction is mainly coursed by a viscosity of a gearbox oil. Viscosity is lower at higher temperature.

Clutch itself have a minimal drag and a clutch plate have rather big diameter and weight. All that leads to rather high inertia of that moving parts.

So imagine that the clutch plate is spinning at 1400rpm and suddenly got stooped. You get the bang (like in all modern wet-clutch motorcycles).

When oil is cold there is no problem become the high viscosity of oil. Generally higher viscosity less bang. I'm using  85W140 ENI ROTRA MP oil and as far I've tested, it is the best oil for my gearbox. Oil tested at temps down to 32*F.

Pulling in the clutch for at least 15s before putting the first helps a lot. There is time to slow down the clutch plate. However, I've noticed that after a log time in traffic jam when engine had 257*F I had to wait 2 minutes to putt into first without the bang.

Factory oil is to thin in that temperature and there was no way to force the clutch plate to slow down. The same was with Redline Heavy.

I've done more than 12k miles using high viscosity oils and any abnormal wear wasn't noticed at all.

 

There is also one more trick that I use to up down shift without any sound. This is also the result of using this kind of a gerbox with dry clutch.

I noticed that the gerbox clunk more when I disengage the clutch fully. When I just pull the lever as far as half of an inch in the clutch starts to slip and that the point when you change the gear up. Plus throttle close-open bleep you can have a great results. It needs some practices but when You get it You will noticed the difference. It is not a gear change without the clutch. Clutch is half engaged eliminating the revert bounce of the slowing down gears due to the constant momentum applied. 

Some say that applying a force on the gear change lever will decrees the bang. Generally it is not true on single clutch Guzzi. Don't do it, otherwise an increase shift drum wear can be noted.

 

I can describe in more detailed way, with pictures and stuff, what happens in the gerabox and why they clunk, if any of the forum user want an explanation.

 

Above mentioned methods was tested on 2 Stelvios and one Griso with the same results.

 

Chris

 

P.S. Sorry for my English.