Narrow frame vs std frame width

[Burns310r]

Whats the advantages to the narrow frame

Im currently running a stock frame with +3 A-arms and 4+1 rims to make me near 50"

Bike handle corners very very well.


When looking at a CR500 link setup (been probing here for a few days on them) I notice that all the ones i have been seeing are narrow width.

This means that my front end will only be 48" in the front. Anybody run this setup? Im worried about taking a step backwards in handling in the front. Obviously my rear end wil be much much better.

Will this also change the spring rate and valving needs for my front shocks? I would assume it would as the shock mounts would 1" closer to the frame than they would be on my current setup.


Thanks for the advice/info in advanced.

Burns

[muddymess]

the narrow frame is only an advantage for XC racing as it lets you run longer A-arms and keep the same width so your not snagging trees

[250Renvy]

Originally posted by muddymess
the narrow frame is only an advantage for XC racing as it lets you run longer A-arms and keep the same width so your not snagging trees

Not 100% true. The narrow frame was built to allow longer shocks and having more adjustability and valving. When they were originally designed, shocks were not as advanced as they are now, which is why they are not as common. It also affects camber in the stroke as seen on Kawasaki's website on the KFX. The new YFZ's are also narrow frame designs.

Some say there is more body roll with narrow frames.

The problem burns, is that there are not very many stock front CR500 link frames out there used, so it's one or the other in most cases. Stock link stock front or narrow front, CR500 link.

The narrow front will bring your front end in 1" on either side, but everything is moved in, including shock mounts making the setup the exact same as stock, just closer so everything will bolt up and work as is.

[Burns310r]

Im doubting i will notice a difference from 50" front end to a 48" front end.


Im very close to spending some money on this setup....


Anybody else have any convincing reasons that a CR500 link is amazing on the MX track. HAHA.

[89trx250r]

http://www.exriders.com/vbb/showthread.php?threadid=418550

[89trx250r]

also youll be running +4 aarms so youll still be 50 inches in the front

[Burns310r]

I will be running +3 Arms in the front... not sure where the +4 came from.

[89trx250r]

oh my mistake i was under the impression mostly all the narrow frames were sold with a +4 front end due to the loss of 1 inch between the frame rails

[Burns310r]

They may have been sold with them....haha..


I have a set of Gibson +3 LT arms that work pretty well. Id love to have a Protrax front end, but.....$$$$$$......

[mx Eli]

personally I like to have my quads right at the 50" mark in front, some people like to have it at 48. I know 3-2 rims are not the best for handling but in your case I would try and borrow a set from sombody and see how much it affects you, that is before you buy +4 a arms.

[Burns310r]

Ya i could buy different front rims, at the chance of more bump steer.



I will probably just run 48" wide and see how things work out.

[sangheraent]

doesn't bump steer get reduced with a stabilizer?

[D Bergstrom]

Originally posted by Burns310r
Ya i could buy different front rims, at the chance of more bump steer.

Bumpsteer is the change in toe thoughout the suspension travel, rim offset has no effect on it. You will feel a little more feedback though the bars with a wider offset wheel, since more of the wheel sticks out beyond the hub, hence more leverage on the spindles.

I switch back and forth between 4:1 and 3:2 wheels on my 250R depending on how wide I need to be. I notice a difference, but nothing major. I feel the extra width is worth the minimal extra feedback I feel through the bars. I would do what mx Eli suggested, find a set of 3:2 wheels and at least try them, you may find out you like 50" better, but you may also find you like 48" more. Test to see what works best for you.

Regardless of what your front width ends up being, adjust your rear axle to make your rear width slightly narrower then the front width, helps with cornering. A wider rear width will make the quad want to push in corners.

Doug

[danhung11]

Originally posted by 250Renvy
Not 100% true. The narrow frame was built to allow longer shocks and having more adjustability and valving. When they were originally designed, shocks were not as advanced as they are now, which is why they are not as common. It also affects camber in the stroke as seen on Kawasaki's website on the KFX. The new YFZ's are also narrow frame designs.

Some say there is more body roll with narrow frames.

The problem burns, is that there are not very many stock front CR500 link frames out there used, so it's one or the other in most cases. Stock link stock front or narrow front, CR500 link.

The narrow front will bring your front end in 1" on either side, but everything is moved in, including shock mounts making the setup the exact same as stock, just closer so everything will bolt up and work as is.

It depends on who you talk to, but 250Renvy hit it on the head. Shocks these days are really amazing compared to what type of shocks available when aftermarket frames were the allowed in Pro ranks. I'd think the body roll would also be affected by make/model of the bike, and where the weight of the chassis is. I've visited with Mike Walsh and Mark Laeger about this exact same thing, and respect both of their opinions.

At any rate, I think the average weekend racer will hardly be able tell a difference in the wide vs. narrow on similar machines. My Laeger is actually a CR500 Rear with Wide Front Plus 3 ProTrax. :D

BTW - good information going on throughout... :chinese:

[matt250r21]

I have both stock width and narrow Laegers Rs. I can tell you the narrow may have a touch more roll in the corners and may be a little better thru the rough stuff. If you shocks are setup both styles are winners.

With a narrow frame and +4 arms you will still need 3+2 rims depending on your camber setup to get to 50 wide.

One other thing, when you switch to the CR500 setup your going to be kicking your self for not doing it sooner.

[Lasher]

When I first tried my Walsh narrow chassis, all I had was 3+2 rims. It was really wide (close to not making it through the spreader bars).

The following race I got 4+1 rims and it made a difference in the cornering. Granted the tires were also changed, but it felt more responsive.

[mx Eli]

I do not personally know this fro sure but from reading on here it seems like a narrow frame requires +4 a arms with 4-1 rims to be at 50 inchs and a regular (or wide) requires +3 with 4-1 rims. so with a narrow frame and +3 a arms and 3-2 rims would be at 50, it might also depend on the chassis brand (walsh, leager)

While on the topic who all made narrow frame's besides walsh and leager?

With what 250rrenvy said, he made a good point about having longer shocks and a arms but i was thinking the idea of narrow frame might have been thought of by trying to get the a arms to be longer and the shock mounts being moved was almost just a by product. correct me if I'm wrong but +4 and +3 a arms have the same length shocks, just are valved for added leverage? If sombody had the same brand a arms in +3 and +4 it would be cool to see if the 1 inch is made up after the lower shock mount or before

like I said I'm not an expert and only 15 soo this may not be rigth:p

[dustin_j]

Originally posted by D Bergstrom
Bumpsteer is the change in toe thoughout the suspension travel, rim offset has no effect on it. You will feel a little more feedback though the bars with a wider offset wheel, since more of the wheel sticks out beyond the hub, hence more leverage on the spindles.

I switch back and forth between 4:1 and 3:2 wheels on my 250R depending on how wide I need to be. I notice a difference, but nothing major. I feel the extra width is worth the minimal extra feedback I feel through the bars. I would do what mx Eli suggested, find a set of 3:2 wheels and at least try them, you may find out you like 50" better, but you may also find you like 48" more. Test to see what works best for you.

Regardless of what your front width ends up being, adjust your rear axle to make your rear width slightly narrower then the front width, helps with cornering. A wider rear width will make the quad want to push in corners.

Doug

Good info here!

[C41Xracer]

Originally posted by mx Eli

While on the topic who all made narrow frame's besides walsh and leager?




someone will have to help me with the name of the company and chassis but Johnny Gahlager Sr. made a narrow front R chassis back in the day. I have one

[addictedtomud]

Roll Design and Predator frames both had narrow fronts. Roll was a no-link rear, Predator was a copy of Laeger, so it had CR500 rear.

[mx Eli]

predator as in polaris predator? umm the 03 a buddy has is a no link...

[addictedtomud]

No Predator was an aftermarket frame maker in the early 2000's. The frame I had was stamped '03' and it was a laeger copy. This is what Gallagher was running from what I understand - maybe I got the name wrong, tho! Anybody else weigh in on this? Rich?

[250Renvy]

I think predator is correct.

There is also Lovins performance chassis' that were narrow CR500 direct Laegers copies.

[C41Xracer]

yes its a predator chassis, i looked when i got home. Yes this is the chassis Gallagher was running.

[fish10782]

I'm running a narrow frame cr500 linked hybrid crf450. I absolutely love it. My other r is a no link aarens framed and the 500 link seems way smoother. I didn't notice any difference in handling with the roll design +3 set up on the narrow frame. However when I put a set of 400 ex a arms bump steer was horrible....