Jump to content

Maxton rear shock.


marktheaxeman

Recommended Posts

On 12/1/2021 at 1:13 AM, docc said:

So, +1 on raising the forks in the triple trees. I settled on 5mm on my RedFrame Sport. Also, best practice to spec the springs, front and rear, for your weight in gear and "riding style." Tire selection and tire pressures also will affect stability.

@marktheaxeman, I seem to recall your V11 Sport is a 2001 Short/RedFrame (rather than a 2002/longframe as shown in your profile). You should have no trouble with "twitchy steering" with a slightly longer shock and the proper spring rates, tires/pressures. Once set up, you can "tune" the trade-off between quick and twitchy by adjusting the fork height in the triples.

If you had a VERY early V11 Sport. That triple tree angle might be less forgiving. Your 2001 should be fine.

 

I agree to this. Before investing large amounts in changing the geometry, I would suggest you use the possibilities to adjust within the current range. I changed from Dunlop (very stable) to conti roadattack 3, this was day and night, just like one of the magazines promised. Further, I followed the advise from this forum to change from 180/55 to 170/60 for the rear tyre.  But this last one is only for the long frames. You propably have a 160/60 tyre at the rear.

 

  • Like 1
Link to comment
Share on other sites

1 hour ago, motortouring said:

I have the original Sachs (on a longframe), but that is really far from any speedweave. Either with luggage or without. At what speed is the weave approximately, usually around 140-160 km/hour, isn't it?

Yes, I typically found it around 145 kph/ 90 mph passing a semi-tractor-trailer rig on our interstates. I found it to be from a combination of factors: the factory Pirelli Dragon tires were soft combined with low tire pressures (33 fr/ 37 rr),  spring rates too soft for my weight, too much "sag"/ too little preload (especially the rear), too little damping. Increasing the damping on the steering damper made this worse. All combined with the short RedFrame (yet, this one does not have the suspect earliest triple trees with the alleged 0,5º steeper rake).

In short, it was just too soft in every way to be stable in those conditions at that speed.  Addressing all of these contributors solved the weave entirely without introducing any twitch or wobble.

  • Like 1
Link to comment
Share on other sites

4 hours ago, docc said:

Yes, I typically found it around 145 kph/ 90 mph passing a semi-tractor-trailer rig on our interstates. I found it to be from a combination of factors: the factory Pirelli Dragon tires were soft combined with low tire pressures (33 fr/ 37 rr),  spring rates too soft for my weight, too much "sag"/ too little preload (especially the rear), too little damping. Increasing the damping on the steering damper made this worse. All combined with the short RedFrame (yet, this one does not have the suspect earliest triple trees with the alleged 0,5º steeper rake).

In short, it was just too soft in every way to be stable in those conditions at that speed.  Addressing all of these contributors solved the weave entirely without introducing any twitch or wobble.

How do you identify these docc? Do all the later trees have the same geometry until the end of the V11's?

Ciao

Link to comment
Share on other sites

1 hour ago, Lucky Phil said:

How do you identify these docc? Do all the later trees have the same geometry until the end of the V11's?

Ciao

Yes, all V11 after about January 2000 have the same geometry.  The part numbers are cast into the bottoms of the triples. They are hard to see. That “Geometry” thread I linked above has the details on the part numbers. Also, there is a post showing @footgoose’s January 2000 Sport that has the early triples, while my March 2000 has the later parts.  (Not that Guzzi is known to make changes at a specific date or point in production.)

Link to comment
Share on other sites

1 hour ago, docc said:

Yes, all V11 after about January 2000 have the same geometry.  The part numbers are cast into the bottoms of the triples. They are hard to see. That “Geometry” thread I linked above has the details on the part numbers. Also, there is a post showing @footgoose’s January 2000 Sport that has the early triples, while my March 2000 has the later parts.  (Not that Guzzi is known to make changes at a specific date or point in production.)

I just re read that whole thread docc and at the end of the day there seems to be no conclusive evidence that the clamps were changed apart from some numbers which at the time I couldn't identify on my bike. I'll have another look today.

I only ask as I want to fit the later top clamp to my bike. I'd be surprised if Guzzi actually went to the trouble of producing a set of triple clamps with fork bores not aligned with the steering stem axis to the tune of 1/2 degree. I've had bikes with this set up from the factory ( My RC30 Honda had it from memory) but it's a bit unusual esp as an afterthought attempt to solve a handling issue. You generally change the offset to correct a problem. My 1198 has Dan Kyle 30mm offset triple clamps as opposed to the std 36mm offset to improve the steering.

If anyone has a set of the later clamps or even the upper clamp like shown below I'd be interested. I can also then do a forensic measurement and put this to bed once and for all, maybe:)

$_3 (2).jpg

Same as this but without the holes open holes.

s-l1600.jpg

Ciao

Link to comment
Share on other sites

Apparently, there was an early service bulletin on the early V11 Sport triple tree issue, but no one has ever produced it for us. It was Greg field that initially brought this to our attention. I put a lot of credence into his insights. He was in a unique position at Moto International, Seattle WA/USA, to have access to source documents and actual service experiences.

From our observations at that SpineRaid, it appears the early triples were leftover from the 1100 Sport-i and that the change was. indeed, an attempt to correct a problem (early reports of instability of the RedFrame).

Link to comment
Share on other sites

Best measure I can get eye to eye on my 2000 Sachs is 278mm. My Öhlins paperwork states 286mm "Shock Absorber Length" (assuming that is "eye to eye?").

So, 8mm?

(This is an Öhlins factory unit, MG 127, not the V11 Öhlins shock from Scura, Coppa Italia, Café Sport, etc.)

Link to comment
Share on other sites

On 12/3/2021 at 10:30 AM, docc said:

Apparently, there was an early service bulletin on the early V11 Sport triple tree issue, but no one has ever produced it for us. It was Greg field that initially brought this to our attention. I put a lot of credence into his insights. He was in a unique position at Moto International, Seattle WA/USA, to have access to source documents and actual service experiences.

From our observations at that SpineRaid, it appears the early triples were leftover from the 1100 Sport-i and that the change was. indeed, an attempt to correct a problem (early reports of instability of the RedFrame).

Gregs info was also that basically any early bike with an axle nut had the old steeper triple clamps. My bike has the later 501452 top clamp ( very hard to find number as its up next to the ignition switch) so either Gregs wrong OR my bike has updated triple clamps with the old style forks? Not sure. If I pull them off I can measure them on the surface plate.

Ciao 

  • Thanks 1
Link to comment
Share on other sites

1 minute ago, Lucky Phil said:

Gregs info was also that basically any early bike with an axle nut had the old steeper triple clamps. My bike has the later 501452 top clamp ( very hard to find number as its up next to the ignition switch) so either Gregs wrong OR my bike has updated triple clamps with the old style forks? Not sure. If I pull them off I can measure them on the surface plate.

Ciao 

Hmm, wait . . . I thought he said a nutted axle (like mine) has the later (canted?) triples. Earlier screw-in axles "might" have the questionable (carry-over?) triples?

Link to comment
Share on other sites

2 hours ago, docc said:

Hmm, wait . . . I thought he said a nutted axle (like mine) has the later (canted?) triples. Earlier screw-in axles "might" have the questionable (carry-over?) triples?

Greg Field quote from earlier post.

Guzzimoto: You are understanding me correctly. The later triple clamps include a 1/2-degree of cant compared to the steering axis. These gray "canted" triple clamps were used through the end of the red-frames. In general, if your red-frame's forks have an axle nut, they also have the early non-"canted" clamps and if your red-frame has an axle that screws directly into the fork leg, it has the "canted" clamps. There is some crossover between axle-fixing arrangements and clamps, though, and Guzzi offered a kit of the "canted" clamps for people who wanted to reduce twitchiness of their early bikes, so any combination of parts is possible. Rosso Mandellos had black "canted" triple clamps. Starting with the LeMans, Guzzi again fitted non-"canted" clamps, but they were painted black.

Still not definitive. I have see a "kit" from Guzzi with a pair of clamps but not sure of their dimensions. Note the "kit". Not sure if it means anything.

https://www.stein-dinse.biz/product_info.php?language=en&products_id=60733

 

Ciao 

  • Thanks 1
Link to comment
Share on other sites

Ah, thanks for that. I should have done my homework. Seems I have a "crossover" set-up. (nutted axle and later triples)

Also, I searched the Workshop Manual for the shock dimensions. Nice line drawing s of both the Sachs-Boge and White Power (which, to my knowledge was never fitted to a V11), but no dimensions. Lots of nice dimension drawing of the frame, subframes and swingarm, but not the shock length.

Perhaps someone else can check my work on the shock lengths I posted . . .

Link to comment
Share on other sites

5 hours ago, docc said:

Ah, thanks for that. I should have done my homework. Seems I have a "crossover" set-up. (nutted axle and later triples)

Also, I searched the Workshop Manual for the shock dimensions. Nice line drawing s of both the Sachs-Boge and White Power (which, to my knowledge was never fitted to a V11), but no dimensions. Lots of nice dimension drawing of the frame, subframes and swingarm, but not the shock length.

Perhaps someone else can check my work on the shock lengths I posted . . .

Well you certainly have the 278mm correct docc for the std shock. My bike must also be a "crossover bike" then as well.

Ciao

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...