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Discussion Starter #1
G'day All,
Some may have read here about the quirk in handling that I have with my 2000 F4 750 Through corners it wants to fall into the corner. That is when you go into a left hand corner then I have to push quite hard on the left hand bar to keep it from wanting to steer in on its self. When going through a right hand corner then I have to push hard on the right hand bar. A concerted effort has to be made to keep it steered out of the corner. My son has a 99-2000 F4 750 as well and his is perfect through corners. Mine has had new tyers, suspension settings returned to factory specs then variations tried. Forks have been up and down through the triple clamps, spring ride heights moved about but it still does the same, nothing changes.

I have oft read in magazines etc. that F4s have adjustable rake but have not seen any where how it is ajusted.. Can some one point me in the direction to where and how this is done

I have been riding 50s, 60s and 70s British bikes for 48 years as daily transport. My sons Ducati and MV also all go very easily around corners, the bars can be held between fingers and thumbs and they just waft around. Why won't my MV?
 

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Have you checked your ride height with the Link Rod Screw? It might be set too high -- too far turned out. What about having your suspension configured to your weight? Also, tire pressure to 33?
 

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Idea... pick a common visual marker on each bike towards the furthest point near each brake light. Drop a measurement from that point to the ground while holding each bike straight up. Try this without sitting on each bike. If your bike measurement is greater than your son's bike then your ride height is set too high, too great -- given you said his bike rides well for you and it's the same model.

UPDATE:
Check this image posted by Alex on his store. It's an easy reference to help visualize the ride height linkage. (Suspension Link Rod)
https://mygpracing.com/product/suspension-link-rod-f4-pre-2010/
 

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This "potentially" sounds like a frame geometry issue. Do you know the history of the bike? - Was it involved in a small crash?

New tyres and updating the suspension will highlight a problem that may be masked earlier.
 

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On the other end of the bike have you checked the health of the steering bearings and stem?
 

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Discussion Starter #6
Thanks for the replies guys. I have set the bike back to factory suspension settings and started from there. The ride height has been varied incrementally up and down including with me aboard. I don't know the history of the bike but the fact that it is the same both left and right, not biased one way or the other, tends to say all is straight with it. My previous experience with steering head bearings is that they become notchy, balls or rollers dropping into divots, but there is no eveidence of this even with the front end suspended. Oh, I forgot to mention that the book says 33 PSI tyre pressure front and back but I have incrementally gone up to 42 PSI front and back and variations of.
Googling this problem shows that I am not alone with this with others having the same problem with different bikes.

Ken.
 

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Check your ride height again.
42psi in your tyres is way too high for a MV.
Stick to 33 as the manual suggests.
I don't understand part of your comment
You say when you tip the bike into a L/H corner and push on the L/H bar (countersteer)
that will make the bike tip over further.
Well that's what countersteering does on any bike.
You are making the bike lean over further.
So I don't get your problem.
 

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Countersteering aside: How are your front calipers working, evenly between the two? Is one not working? Are you braking into turns?
 

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Discussion Starter #9
Check your ride height again.
42psi in your tyres is way too high for a MV.
Stick to 33 as the manual suggests.
I don't understand part of your comment
You say when you tip the bike into a L/H corner and push on the L/H bar (countersteer)
that will make the bike tip over further.
Well that's what countersteering does on any bike.
You are making the bike lean over further.
So I don't get your problem.
G'day Mitchy. Whilst going through a LH corner I have to maintain heavy pushing preasure on the LH bar, its pushing back against me If I relax that pressure then the bike will rapidly and increasingly run in towards the inside of the corner. If I want to take a wider line through the corner it takes a fair bit of pressure (push) to make it run wider. It takes concerntration and a fair bit of effort to keep it from running right into the inside of the corner, into the dirt. Same thing on RH corners. Now, on my Norvin, Vincents, BSA R3, Ducati Monster 659, my sons MV, Ducati S4R, Ducati 600 Monster, once they are in the corner, I can hold the bars between thumb and fore finger and they just waft around. If I was game enough I am quite sure that I could go around with my hands right off the handle bars.



Ken.
 

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Discussion Starter #10
Countersteering aside: How are your front calipers working, evenly between the two? Is one not working? Are you braking into turns?
Not braking into turns Edward, just riding around open road corners. It will do it on small slow in town corners as well. The only difference I have noticed with the braking between the two is that my sons MV seems to have a more solid lever, mine a softer lever. Under similar braking my front brake lever comes further back and is a touch softer, his lever is further out and a touch harder.


Ken.
 

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Recheck your brakes are working evenly. Bleed them, it's simple.

Next... triple clamps/head. Have you removed the clamps to have them inspected? Like @cruiser wrote a crash may have occurred sometime during the bike's history. Suspicion is your front wheel is out of alignment.

(Mind this is for a dragster but full of info)
1.
https://www.mvagusta.net/forum/56-suspension-brakes-tyre-tech/142114-wheel-alignment.html#post1526650

2.
https://www.mvagusta.net/forum/56-suspension-brakes-tyre-tech/142114-wheel-alignment.html#post1527610

3.
https://www.mvagusta.net/forum/56-suspension-brakes-tyre-tech/142114-wheel-alignment.html#post1551794
 

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How about your Steering damper?

Hi!


I had exactly the same experience when I first got my SR .. It would want to "Drop into corners" at slow to moderate speeds = al lot of countersteer. It turned out to be a combination of geometry (too high ride-height and too hard suspension setup for my weight and height) -- But most of the problem was that the steering damper was set way too hard ..
 

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Hope I'm not overstating the obvious, but does the bike have mis-matched tyres? (I don't disrespect your biking experience:wink2:)

Depending on brands, this can make one heck of a handling problem.
 

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Discussion Starter #14
Hope I'm not overstating the obvious, but does the bike have mis-matched tyres? (I don't disrespect your biking experience:wink2:)

Depending on brands, this can make one heck of a handling problem.
I have matching front and rear tyres on my F4 and initially thought that my sons bike had a different brand but when I looked he had the same same tyres.
 

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Discussion Starter #15
Hi!


I had exactly the same experience when I first got my SR .. It would want to "Drop into corners" at slow to moderate speeds = al lot of countersteer. It turned out to be a combination of geometry (too high ride-height and too hard suspension setup for my weight and height) -- But most of the problem was that the steering damper was set way too hard ..
G'day DK. The ride height on mine is quite low but I have had it set high as well trying different settings. I can't see how thew steering damper would be a cause. A damper is there to prevent severe oscilations of the forks so the slow movement as it is tipped into a corner wouldn't be a problem. Also given the time a bike spends in a corner is quite long compared to the micro seconds that a damper has to damp.


Ken.
 

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Steering Damper

Hi! I'm inclined to agree with you completely, The steering damper should not have any real influence on turning in to slow or medium speed corners, but I assure you that was the case with mine .. My theory is that you actually unconciously do a lot of minute movements with the handlebars as you "negotiate" a corner. (Just like you can not ride a bicycle in a narrow track that just allows the width of the tyres, and go a.. over t..s when you try to ride a tram-line track) If the damper is way too tight, you can not do these small movements, and the bike feels out of control and wants to drop you against your natural counter-steer --- Mind you its just a theory... :grin2: I may have changed other settings or things on top of finding out that the damper was maxed out.
 

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Discussion Starter #17
Hi! I'm inclined to agree with you completely, The steering damper should not have any real influence on turning in to slow or medium speed corners, but I assure you that was the case with mine .. My theory is that you actually unconciously do a lot of minute movements with the handlebars as you "negotiate" a corner. (Just like you can not ride a bicycle in a narrow track that just allows the width of the tyres, and go a.. over t..s when you try to ride a tram-line track) If the damper is way too tight, you can not do these small movements, and the bike feels out of control and wants to drop you against your natural counter-steer --- Mind you its just a theory... :grin2: I may have changed other settings or things on top of finding out that the damper was maxed out.
I will give it a go DK, its easy to do.
 

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If you go to the Dave Moss website and search for your issue,or even send him an email.
He is a suspension guru.
But he will want measurements starting with static sag etc.
 

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Hey,not sure if you have rechecked the wheel balance in your endeavours because it sounds similar to the effect I was getting when the front wheel on my 1090 RR lost one of its balance weights. My bike was dropping into turns quite scarily and I can only guess it was the gyroscopic force of the unbalanced wheel. Not sure if there is anything else that could upset the gyroscopic force of the front wheel but checking the wheel balance is fairly easy, I couldn't believe how much it was affected by the wheel weight being missing.
 

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Just to add to the speculation and tips.
No F4 has adjustable steering head unit.
Front brakes are connected to one solid axle, mounted rigidly to the forks, one brake being more efficient than the other can not affect steering.

Increase front suspension pre-load, see if this makes a difference mate, change one thing at a time and do so in big amounts. Don't just increase pre-load by one turn, do a few but keep note of what you're doing.

Good luck
 
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