Author Topic: Low speed turn in, why?  (Read 1435 times)

stuo

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Low speed turn in, why?
« on: April 27, 2018, 03:07:23 AM »
I have two 2008 GV 250's; one steers fine, the other wants to turn in at low speeds. Anybody have suggestions as to what the cause and cure might be?
2009 GV 250

Viper254

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Re: Low speed turn in, why?
« Reply #1 on: April 27, 2018, 06:49:13 AM »
checked the  front tyre pressures on both bikes?
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Suzuki GW250 Inazuma (2016)
Honda C70C (red, 1983)

CROSSBOLT

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Re: Low speed turn in, why?
« Reply #2 on: April 27, 2018, 12:52:09 PM »
I do not understand the term, "turn in" at low speeds. Could you explain, please?
Karl

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ophelia

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Re: Low speed turn in, why?
« Reply #3 on: April 27, 2018, 05:28:05 PM »
How's the pattern of tire wear on the front and rear tires?

Tires can transform a bike's handling.
2011 Kymco Downtown 300i

stuo

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Re: Low speed turn in, why?
« Reply #4 on: April 27, 2018, 06:12:10 PM »
Thanks for the replies. By "turn in" I mean the front wheel wants to go right or left, the "chopper effect". Too much forward rake? If my other GV250 didn't steer so much better it wouldn't bother me because it isn't noticeable once it's moving above 15mph or so.

Yes, I did check tire pressure, even went incrementally from 25 up to 35 pounds in the front. No help. The front is a new Michelin, the rear an older, slightly worn Michelin (30 pounds pressure).

I just acquired the bike, which has 16K miles on it, runs and looks great otherwise. Maybe there's a reason it was only $875, heh heh.
2009 GV 250

CROSSBOLT

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Re: Low speed turn in, why?
« Reply #5 on: April 27, 2018, 06:41:50 PM »
"Heh, heh!" You bet! You dint buy it, you stole it! I think I understand it sharpens the turn when slow, right? Tightens the turn uninvited.
Karl

Three motorcycles 1960-1977 (restored a 1955 BSA)
Agility 50
Yager 200i
Downtown 300i
Navy tech, Ships Engineer, pilot and aircraft mechanic

Stig / Major Tom

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Re: Low speed turn in, why?
« Reply #6 on: April 27, 2018, 06:50:46 PM »
Thanks for the replies. By "turn in" I mean the front wheel wants to go right or left, the "chopper effect". Too much forward rake? If my other GV250 didn't steer so much better it wouldn't bother me because it isn't noticeable once it's moving above 15mph or so.

Yes, I did check tire pressure, even went incrementally from 25 up to 35 pounds in the front. No help. The front is a new Michelin, the rear an older, slightly worn Michelin (30 pounds pressure).

I just acquired the bike, which has 16K miles on it, runs and looks great otherwise. Maybe there's a reason it was only $875, heh heh.
Something bent?
Steering head? frame?
Was it used in a circus?

Stig
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stuo

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Re: Low speed turn in, why?
« Reply #7 on: April 27, 2018, 09:34:46 PM »
 "Was it used in a circus?" Hmm, interesting question. Are there any circuses anymore? You think maybe an elephant sat on it...or rode it? That could have bent the fork forward.

 I checked out the tire wear, Mr. Robot: it looks normal.

There is no sign of damage but if it was wrecked it doesn't seem likely that a crash would give the front wheel/fork forward rake. The opposite seems more likely, the front wheel and fork would be bent back giving the steering more caster and therefore the steering would tend to want to go straight, no?

I will contact Mike the Master (mjr) to help me on this and report the results. Don't touch that dial. 
2009 GV 250

LidoCA

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Re: Low speed turn in, why?
« Reply #8 on: April 28, 2018, 06:08:47 AM »
 If it hasn't been damaged, check the tire like others have said. My SMAX started having problems with tracking properly. I replaced the front tire and the problem went away.
Steve
I have ridden well over 17 miles on my scooters.

2013 LIKE 200i LX.
2016 Yamaha SMax
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stuo

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Re: Low speed turn in, why?
« Reply #9 on: April 28, 2018, 05:49:08 PM »
Thanks, Steve,

I suspect you have the answer because the bike shows no damage and the fork is not loose or binding. And now that I'm thinking about it I have experienced some front wheel shaking on this bike.

I'll try a new tire and report back.

Stu 
2009 GV 250

Viper254

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Re: Low speed turn in, why?
« Reply #10 on: April 29, 2018, 10:33:41 AM »
If you have two of the same bike, the cheapest way to diagnose would be to swap the front wheels over and see if there's any behavioural change.
Rides;

Suzuki GW250 Inazuma (2016)
Honda C70C (red, 1983)

Stig / Major Tom

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Re: Low speed turn in, why?
« Reply #11 on: April 29, 2018, 08:17:07 PM »
Perhaps we were too quick to rule out circus abuse, yes?

In the first release of the movie, "Water for Goats", there are several scenes where we can see a 10 yr old GV 250 being abused in Naples by both of the Benzini Brothers. Benito easily goes 175 kilos and brother Nick is somewhat heavier.

This movie was re-released as "Water for Elephants" and some of the scooter scenes have been deleted. However, I'm running your VIN with the circus curator - but I am convinced.....

s t i g
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And, I'm feeling a little peculiar.

stuo

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Re: Low speed turn in, why?
« Reply #12 on: April 29, 2018, 09:21:23 PM »
Sorry to rain on your circus parade, Stig, but that wasn't the correct answer. Worth honorable mention, though, for creativity and applied historical and cultural knowledge.

After acting on the Viper's great suggestion I switched front wheels on my two twin GV250's; same damn result!

Then a bolt of brain lightning struck. When I  bought the first GV I immediately removed the lumbar support so I could sit farther back. I have not done it to the recently acquired ("stolen") GV so I am forced to sit uncomfortably closer to the front of the scoot, thereby making the front end considerably heavier then I was used to, and making the steering much harder at low speeds.

Two solutions: Remove the lumbar support and move my lard-ass back...or do a little weight lifting,  muscle up and ride with my nose on the windscreen. I vote for the former.

The take-away knowledge gained from my problem: seating position fore and aft has a significant effect on front end loading. Moving backwards about two inches on a GV 250 and the difference in steering is very apparent. I recall reading in some scooter owner's manual the admonishment to sit close to the front of the scoot. I wondered why that was mentioned. Perhaps to keep the front tire firmly gripping the road?  Hmmm...
2009 GV 250

Stig / Major Tom

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Re: Low speed turn in, why?
« Reply #13 on: April 29, 2018, 10:35:56 PM »
When encountering a particularly rough bit of road I always slide forward a bit to share more weight with the front tire and suspension. Seems to lessen the beating from the rear suspension. I have a long seat, and sit further back in normal riding.
Not cornering on the rough stuff, so no idea if moving forward alters steering feel.

Stig
Boston Strong
Rural Ohio

And, I'm feeling a little peculiar.

Viper254

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Re: Low speed turn in, why?
« Reply #14 on: April 30, 2018, 07:18:05 AM »
Glad you found the issue! Scooters do tend to be a little lighter at the front end so need the body weight forwards for good weight distribution sometimes :)
Rides;

Suzuki GW250 Inazuma (2016)
Honda C70C (red, 1983)

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