DR650 turned into SM, now has a problem - Page 2

Rider · 05-20-2009, 02:34 PM

Quote:

Originally Posted by cuttle

he could try dropping the rear shock in the lower position - it's easy to do, free and doesn't take all that long.

No guarantees that it will help thou...

The guy is short(5'7") so he says the rear shock is at the lowest setting.

BobTheBiker · 05-20-2009, 02:47 PM

he either needs longer fork tubes to compensate for the 2" change in height, lowering links to put the rear lower and compensate for it, or he's just not going to experience a good ride at that speed.

checking the steering head bearings is a good idea regardless though. at least inspect for good condition and grease appropriately as needed. a steering damper would probably not hurt either.

6doublefive321 · 05-20-2009, 03:20 PM

I'm saying its the geometry. My SM has been lowered a couple inches, and it gets a little wiggly at high speeds. By putting on smaller wheels, the fork angle has been steepened, which makes it much "quicker" on turn in, but also more unstable. A lowering link in the back should fix it up. There should be a ton of lowering links for that bike. Also, a steering stabilizer would help. All these comments are assuming that nothing else is messed up, i.e. wheel, head bearings, etc.

zed · 05-20-2009, 05:14 PM

you didn't say what he did for the rear wheel, what was the tire size change. ideally you want to raise or lower both ends roughly the same amount.

pdog · 05-20-2009, 05:45 PM

Just pull it up into a mad wheelie. Front end not on the ground = no front end stability problems.

Sorry, I have nothing to contribute but sympathy for a fellow 'tard.

Rider · 05-21-2009, 08:35 AM

He was looking at his bike last night and noticed that he had about 2 inches of thread on the shock so he is going to adjust the ride height. Cranking that shock spring tighter is going to make for a real stiff ride though.

I suggested he try to find a rear shock from a DRZ400 SM. I'm sure that is a shorter shock.

Rsv1000R · 05-21-2009, 09:09 AM

Quote:

Originally Posted by Rider

He was looking at his bike last night and noticed that he had about 2 inches of thread on the shock so he is going to adjust the ride height. Cranking that shock spring tighter is going to make for a real stiff ride though.

I suggested he try to find a rear shock from a DRZ400 SM. I'm sure that is a shorter shock.

He'd want a shorter spring. He can however crank it down to see that it does cure the problem before going out and buying a shorter spring.

Gas Man · 05-21-2009, 03:47 PM

Most likely he screwed the trail up, making the bike unstable.

Tell him to check it using a rake and trail calculator

This one has more info
http://www.rbracing-rsr.com/rakeandtrail.html

But this one is a bit easier to use.
http://www.goldammercycle.com/hispeed/rakeandtrail.php

Don't tell me its cruiser/chopper shit. Its all about geometry.

Further for balance issues... go dyna beads and STU
http://lowdownchopshop.com/shopping-cart/14.html

Rider · 05-21-2009, 03:55 PM

He is going to get some lowing links and drop the ass end 2" to bring it back to the OEM rake.

Trip · 05-21-2009, 03:56 PM

put some nos energy drink in it

05-20-2009, 03:20 PM	#13
6doublefive321 Resident Droog Join Date: Mar 2008 Location: Northern burbs, Atlanta Moto: 625 SMC, '08 Tuono R Posts: 471	I'm saying its the geometry. My SM has been lowered a couple inches, and it gets a little wiggly at high speeds. By putting on smaller wheels, the fork angle has been steepened, which makes it much "quicker" on turn in, but also more unstable. A lowering link in the back should fix it up. There should be a ton of lowering links for that bike. Also, a steering stabilizer would help. All these comments are assuming that nothing else is messed up, i.e. wheel, head bearings, etc. __________________ I'm sick and tired of being bored.

05-21-2009, 03:47 PM	#18
Gas Man Trip's Assistant Join Date: Feb 2008 Location: Imported from Detroit Moto: 2009 HD Street Classic Posts: 12,149	Most likely he screwed the trail up, making the bike unstable. Tell him to check it using a rake and trail calculator This one has more info http://www.rbracing-rsr.com/rakeandtrail.html But this one is a bit easier to use. http://www.goldammercycle.com/hispeed/rakeandtrail.php Don't tell me its cruiser/chopper shit. Its all about geometry. Further for balance issues... go dyna beads and STU http://lowdownchopshop.com/shopping-cart/14.html __________________ -Chris "Why pay somebody else to fuck up your bike?" Run Amsoil Product

05-21-2009, 03:55 PM	#19
Rider Moto GP Star Join Date: Feb 2008 Posts: 12,156	He is going to get some lowing links and drop the ass end 2" to bring it back to the OEM rake. Last edited by Rider; 05-21-2009 at 03:58 PM..

05-20-2009, 02:47 PM	#12
BobTheBiker too much time on my hands Join Date: Jul 2008 Location: the northern district of god damn Moto: 01 ZX6R, looking for more now. Posts: 1,802	he either needs longer fork tubes to compensate for the 2" change in height, lowering links to put the rear lower and compensate for it, or he's just not going to experience a good ride at that speed. checking the steering head bearings is a good idea regardless though. at least inspect for good condition and grease appropriately as needed. a steering damper would probably not hurt either.

05-20-2009, 05:14 PM	#14
zed yellow don't corner well Join Date: Feb 2009 Location: Kansas City, KS Moto: 06 ZX10R Posts: 1,243	you didn't say what he did for the rear wheel, what was the tire size change. ideally you want to raise or lower both ends roughly the same amount.

05-20-2009, 05:45 PM	#15
pdog Refugee Join Date: Nov 2008 Location: San Francisco, CA Moto: Pimped 2005 SV650 Posts: 332	Just pull it up into a mad wheelie. Front end not on the ground = no front end stability problems. Sorry, I have nothing to contribute but sympathy for a fellow 'tard.

05-21-2009, 08:35 AM	#16
Rider Moto GP Star Join Date: Feb 2008 Posts: 12,156	He was looking at his bike last night and noticed that he had about 2 inches of thread on the shock so he is going to adjust the ride height. Cranking that shock spring tighter is going to make for a real stiff ride though. I suggested he try to find a rear shock from a DRZ400 SM. I'm sure that is a shorter shock.