Jump to content

I feel unstable on my bike


GregC

Recommended Posts

So came to the conclusion that I feel a lot more steady on my slightly scrappy single speed project bike, than I do on my Scott dual suspension.

My Giant singlespeed has a large frame, the Scott has a small frame. The Scott feels like the front wheel wants to fall over to the side, and feels generally "twitchy", but on the giant I feel like i can ride in a straight line at 0.001 kilometers an hour...

 

Any suggestions welcome.

thanks

Link to comment
Share on other sites

It could be that the bigger bike's longer wheelbase offers more stability

or

the angle of the fork together with the trail make a less twitchy front end

 

and other suggestions ?

Link to comment
Share on other sites

Apart from the obvious benefits of getting a Powerbalance band...

 

To compensate for the smaller frame on your Scott, you are probably using a 100mm or possible 110mm stem. The sensation you describe could be the result of this. To confirm this check the lenght of your stem on the Giant

 

A possible cure will be to use a set-back seatpost (say 25mm) and shorten your stem by the same.

Link to comment
Share on other sites

Other possibilities are that the seatpost is too high for the small frame or that the rear suspension bushing/pivots are worn. If you hold the frame and rock the rear wheel there should be no lateral play at all.

Link to comment
Share on other sites

The dish of the wheels?

The wheel axles are 100% in position when you close the qr's?

Head tube angle?

Headset sticky?

The bike is just totally the wrong fit and size?

The Klipdrift effect?

Link to comment
Share on other sites

how tall r u?? how can u ride a large in 1 frame and a small in the other?? seems like u need a frame that fits u.

Link to comment
Share on other sites

Thanks for suggestions.

So far I've given up drinking and ordered a power balance suit from a nice Chinese online store.

 

-Im a +- 1.6m shortass so my 15" Scott feels like the best fitting bike Ive had. The Giant is large because thats the frame that was going, its a project and I have a teeny 50mm stem on it.

-Scott has a 75mm stem, if I sit in riding position, handle bar/stem intersection lines up with axel ( i was always told this is a sizing point?)

-headset seems fine

-pivots etc feel solid, although rear shock isn't as stiff as i feel it should be (i have it pumped slightly harder than my weight rating currently)

-My wheel does appear to be sitting closer to the disc side??

-cant find training wheels in the colour I want

Link to comment
Share on other sites

A shorter stem (and not a longer stem!) will make a bike feel more twitchy because smaller inputs will have larger effects with a short stem.

 

It could be that the Scott just has a more aggressive geometry.

 

FWIW, the first few times I rode my Scott Spark it felt like it was turning in sharper than I had intended. After a few rides I became adjusted to the bike and now it's all good.

Link to comment
Share on other sites

A shorter stem (and not a longer stem!) will make a bike feel more twitchy because smaller inputs will have larger effects with a short stem.

 

It could be that the Scott just has a more aggressive geometry.

 

FWIW, the first few times I rode my Scott Spark it felt like it was turning in sharper than I had intended. After a few rides I became adjusted to the bike and now it's all good.

 

Yeah it was only after mucking around so much on the Giant during diy-chain-tensioner-testing riding around in a small courtyard dodging dogs bowls and dogs that I felt a bit wobbly on the Scott.

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. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Settings My Forum Content My Followed Content Forum Settings Ad Messages My Ads My Favourites My Saved Alerts My Pay Deals Help Logout