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Main Area => General GS500 Discussion => Topic started by: YerrBenny on November 09, 2013, 01:11:55 AM

Title: Front end dropping when letting off throttle
Post by: YerrBenny on November 09, 2013, 01:11:55 AM
I used the search function but can't find the answer to my question

If I am accelerating and I let go the front end of the bike drops forward. What can be my problem??
Title: Re: Front end dropping when letting off throttle
Post by: TheOzTurkish on November 09, 2013, 02:11:36 AM
I wouldn't recommend just closing off the throttle from acceleration, its not an on and off switch, learn to ease the throttle off.

The engine is going from full load (acceleration) to 0 load (closed throttle) and matching the speed of the transmission providing engine braking, its like running full speed and trying to start walking..... you'll stumble over......

how bad is the dipping? if its bottoming out the front forks you may have suspension problems
Title: Re: Front end dropping when letting off throttle
Post by: GS500F2004 on November 09, 2013, 02:27:01 AM
Good explanation OzTurkish, but yea...strange question  :confused:
Title: Re: Front end dropping when letting off throttle
Post by: Banzai on November 09, 2013, 04:18:22 AM
Under acceleration (all cars, bikes etc) the weight shifts to the rear which is presented as the rear springs being compressed. Accelerate hard enough and the front will lift off the ground (a wheelie).

Under deceleration (eg engine braking or using the mechanical brakes) weight shifts to the front. Brake hard enough and the rear will come off the ground (a stoppie).

Soft springs, poor dampers and under-inflated tyres will all increase the effect of this weight shift.

If there are any Physicists on board they could probably use all sorts of scientific formulas to explain this phenomena.
Title: Re: Front end dropping when letting off throttle
Post by: Wagoneer on November 09, 2013, 04:22:02 AM
Just sounds like typical GS soft stock springs and probably old/low fork oil.

And the fact that any bike will dip if you go from accelerating to closing the throttle. Mine used to bottom out under hard braking as well. 0.90 sonic springs and 15w oil helped tenfold.
Title: Re: Front end dropping when letting off throttle
Post by: tialloydragon on November 09, 2013, 05:41:34 AM
+1. The forks shouldn't be diving that much when closing the throttle.

I went with progressive springs and, I think, 20w oil.
Title: Re: Front end dropping when letting off throttle
Post by: YerrBenny on November 09, 2013, 06:18:47 AM

Quote from: TheOzTurkish on November 09, 2013, 02:11:36 AM
I wouldn't recommend just closing off the throttle from acceleration, its not an on and off switch, learn to ease the throttle off.

The engine is going from full load (acceleration) to 0 load (closed throttle) and matching the speed of the transmission providing engine braking, its like running full speed and trying to start walking..... you'll stumble over......

how bad is the dipping? if its bottoming out the front forks you may have suspension problems

Thanks for the explanation. I guess I underestimated the engine braking


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Title: Re: Front end dropping when letting off throttle
Post by: TheOzTurkish on November 09, 2013, 07:29:12 AM
Quote from: YerrBenny on November 09, 2013, 06:18:47 AM

Quote from: TheOzTurkish on November 09, 2013, 02:11:36 AM
I wouldn't recommend just closing off the throttle from acceleration, its not an on and off switch, learn to ease the throttle off.

The engine is going from full load (acceleration) to 0 load (closed throttle) and matching the speed of the transmission providing engine braking, its like running full speed and trying to start walking..... you'll stumble over......

how bad is the dipping? if its bottoming out the front forks you may have suspension problems

Thanks for the explanation. I guess I underestimated the engine braking


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

All good, just yer roll on the throttle and roll off, dont bang it on and off... smoother is faster
Title: Re: Front end dropping when letting off throttle
Post by: radodrill on November 09, 2013, 09:23:20 AM
On my bike I can feel the front springs unload as I roll hard on the throttle (maybe only 1 cm or so actual travel of the shocks) the load up if I quickly roll off.

This is essentially due to your momentum and acceleration.  Your total mass (including the bike) wants to move at a constant speed; when you roll on hard the tire wants to push you faster resulting in more force on the rear end and less on the front thus the front shocks unload.  The opposite holds true for deceleration.
Title: Re: Front end dropping when letting off throttle
Post by: Buckmaw on November 09, 2013, 10:32:00 AM
It's a common issue with this bike.  Mine was cured with a set of progressive springs and adjusting the level of the fork oil.  You might just try adding some oil first before adding new springs.
Title: Re: Front end dropping when letting off throttle
Post by: Dr.McNinja on November 09, 2013, 10:40:51 AM
Quote from: YerrBenny on November 09, 2013, 01:11:55 AM
I used the search function but can't find the answer to my question

If I am accelerating and I let go the front end of the bike drops forward. What can be my problem??

The garbage GS500 front suspension is your problem.

Title: Re: Front end dropping when letting off throttle
Post by: Wagoneer on November 11, 2013, 05:41:24 PM
If I were to do it over again I'd go with a little softer spring and thicker fork oil for daily riding. But I think I'll grow into the .90 springs more and more each season.