[kaizengadi]

Hi Guys,

Recently on my Vstrom SX 250 during a 750 km ride, I noticed that my handle started to wobble starting from low speeds of 30 kmph, whenever I lifted my hands off the handle. The wobbling starts slow and gradually increases to a point of losing control.

To experiment I detached my 45L Aluminium Generic Chinese top box (weight: 5kg empty, 7kg filled) when I reached my hotel. After that I rode nearby and observed that the wobbling issue did not persist even at speeds above 60 kmph.

I am using the stock top rack carrier provided with the Vstrom SX 250, with the top box carrier plate.

1. Is there any way to avoid this behaviour with a loaded top box?
2. Can adding a external top rack carrier solve this issue?
3. What is the general weight a 45L top box loaded with?

[sukiwa]

Originally Posted by kaizengadi

my 45L Aluminium Generic Chinese top box (weight: 5kg empty, 7kg filled)

Is 5Kgs self weight of box and your luggage load is additional 2 Kgs making total weight 7 Kgs? Suzuki recommends maximum of 5 Kgs load, they have pasted a sticker as well.

I am using the stock top rack carrier provided with the Vstrom SX 250, with the top box carrier plate.

How is Top box attached to base plate, do you have a after-market top rack plate? Please share photos.

1. Is there any way to avoid this behaviour with a loaded top box?

Correct mounting of top box and loading of luggage evenly in top box should solve it. Does wobbling get exhibited even when you have hands on handlebar?

2. Can adding a external top rack carrier solve this issue?

Don't you already have a top rack plate?

3. What is the general weight a 45L top box loaded with?

Don't exceed more than 5Kgs for long distance.

[kaizengadi]

Originally Posted by sukiwa

Is 5Kgs self weight of box and your luggage load is additional 2 Kgs making total weight 7 Kgs? Suzuki recommends maximum of 5 Kgs load, they have pasted a sticker as well.

How is Top box attached to base plate, do you have a after-market top rack plate? Please share photos.

Correct mounting of top box and loading of luggage evenly in top box should solve it. Does wobbling get exhibited even when you have hands on handlebar?
Don't you already have a top rack plate?
Don't exceed more than 5Kgs for long distance.

Thanks for the comment,

1. I see that the max weight recommended by suzuki on the stock top rack is <6Kg.

2.



I have attached the top box base plate(black) onto the stock top rack(grey). The top box slides onto the rubber screw.


3.The top box fits snugly and there is no play as such between the base plate and top box once attached. The wobbling stops when I have my hands on the handle bar.


4. Is there any way to increase the limit with after market top rack? Since on weekend trips I would like to carry change of clothes which might add up to 2kg bringing total >6kg.

[iamahunter]

Originally Posted by kaizengadi

Hi Guys,

Recently on my Vstrom SX 250 during a 750 km ride, I noticed that my handle started to wobble starting from low speeds of 30 kmph, whenever I lifted my hands off the handle. The wobbling starts slow and gradually increases to a point of losing control.

For starters, try not to take your hands off the handle while riding.

Originally Posted by kaizengadi

To experiment I detached my 45L Aluminium Generic Chinese top box (weight: 5kg empty, 7kg filled) when I reached my hotel. After that I rode nearby and observed that the wobbling issue did not persist even at speeds above 60 kmph.

I am using the stock top rack carrier provided with the Vstrom SX 250, with the top box carrier plate.

1. Is there any way to avoid this behaviour with a loaded top box?
2. Can adding a external top rack carrier solve this issue?
3. What is the general weight a 45L top box loaded with?

The top box plays with the balance of the bike. As it is high and behind the bike, it disturbs the bike's center of gravity. It kind of acts as a lever against the front of the bike, hence causing an unstable front, especially as the Vstrom itself is a light and somewhat tall bike.

There is no guaranteed way to remove this other than to get rid of the top box.

However, the top box is a very convenient on day or 2 days trip, I would suggest to keep it light as possible.
I have quite a heavy top box on the Versys, however, its mostly empty during movement. I use to store my helmet and riding gear if I have to step away from the bike at some point.
At times I have also noticed that the bike is comparatively stable when the tank is full. Mine has a 20L tank adding good amount of weight at the front to balance it.

[sukiwa]

Originally Posted by kaizengadi

3.The top box fits snugly and there is no play as such between the base plate and top box once attached.

Looks good and removes any mechanical issues.

The wobbling stops when I have my hands on the handle bar.

Hope you have already checked cold tyre pressure?

4. Is there any way to increase the limit with after market top rack?

Just to experiment, I carried school notebooks in my Givi 43L top box on V-strom SX 250. Distance was less than 5 kms and also tried removing hands from handle bar for a short distance as well, bike continued in straight line without any wobble.



Load of notebooks (6 Kgs) showed its presence while taking turns, although being heavy it didn't move much. Below notebooks lies my empty backpack, it might add up some more weight. Plus weight of knee guards and gloves.

In summary, loading up top box didn't lead to wobble for me.

[kaizengadi]

Hi sukiwa,

Thanks for experimenting and sharing the observation. The tyre pressure was set to 24psi front 32psi back (recommend 22,29)

I am suspecting a cone set issue. Will be giving my bike soon for 3rd service, will update if Root Cause found.

[kaizengadi]

Originally Posted by sukiwa

Looks good and removes any mechanical issues.

Hope you have already checked cold tyre pressure?

Just to experiment, I carried school notebooks in my Givi 43L top box on V-strom SX 250. Distance was less than 5 kms and also tried removing hands from handle bar for a short distance as well, bike continued in straight line without any wobble.

Attachment 2462636

Load of notebooks (6 Kgs) showed its presence while taking turns, although being heavy it didn't move much. Below notebooks lies my empty backpack, it might add up some more weight. Plus weight of knee guards and gloves.

In summary, loading up top box didn't lead to wobble for me.

My 3rd service is done, the bill was a whopping 4.7k which was due to bent forks and bent handle bar. This should have exacerbated my handling imbalance due to the excess wight. I redid a another run with few dumbbells and observed the following:

* <= 7 KG - Handle was balanced
* > 9.5KG - Handle vibrates

[Jaggu]

Originally Posted by kaizengadi

* <= 7 KG - Handle was balanced
* > 9.5KG - Handle vibrates

Wind rear suspension tight by one notch and see, that should help stabilise the additional weight at the ends.

[sukiwa]

Originally Posted by kaizengadi

My 3rd service is done, the bill was a whopping 4.7k which was due to bent forks and bent handle bar.

So, this was the root cause.
What kind of riding caused a bend in forks and handle bar? Hope no parking fall or accidents.

[Kalash_6324]

Top boxes messes with the aerodynamics of the bike.
Manufacturers don't really test for the same as it increases the R&D cost by quite a bit.
If you want to go long distances, side mounted boxes are the best option.
Top boxes are generally meant to store something light like your helmet and gear.
Replacement of the bent forks and handlebar will definitely solve your issue to an extent, but considering the fact that the 250 is really light, I doubt the issue will go away completely.

[kaizengadi]

Updates after 4 months:

Fixing my forks and handlebar seems to have fixed my LHS pulling and has stopped the wobbling only below speeds of 50km/hr but above which wobble seems to continue even with empty top box (5.5 kg). Additional weight just increases the amount of wobbling.

Wobbling happens only when hand is lifted off the bars, otherwise I don't feel anything even during cornering. But I have stopped using the top box just to be safe.

Originally Posted by Jaggu

Wind rear suspension tight by one notch and see, that should help stabilise the additional weight at the ends.

I increased the preload to 5th notch (deafault 3), this improved rear suspension feel since I am a bulky guy but wobbling seems to persist.
(Tool used to adjust : ER40 Collet Spanner)

Originally Posted by sukiwa

So, this was the root cause.
What kind of riding caused a bend in forks and handle bar? Hope no parking fall or accidents.

It was a low speed fall (10-15km/hr) during lite off-roading.

Originally Posted by Kalash_6324

Top boxes messes with the aerodynamics of the bike.
Manufacturers don't really test for the same as it increases the R&D cost by quite a bit.
If you want to go long distances, side mounted boxes are the best option.
Top boxes are generally meant to store something light like your helmet and gear.
Replacement of the bent forks and handlebar will definitely solve your issue to an extent, but considering the fact that the 250 is really light, I doubt the issue will go away completely.

Yeah aerodynamics and I feel some resonant frequency at speeds greater than 50km/hr is the problem.