[nathasm]

I have an '04 NRS Air (and two of my buddies are riding the '04 NRS 1) and we're all experiencing similar issues.

When we pedal during rear shock compression, our chainlines skip to a different cog on the cassette. With my Air it's only momentary and it will return back to the designated gear. My buddies have experienced it a bit worse by having the chain fall off.

Is this a poor design, not enough air in the rear shock, or too loose of a chainline, etc....?

Thoughts?
.nathan.

 

[VaNRS2]

I have an '04 NRS Air (and two of my buddies are riding the '04 NRS 1) and we're all experiencing similar issues.

When we pedal during rear shock compression, our chainlines skip to a different cog on the cassette. With my Air it's only momentary and it will return back to the designated gear. My buddies have experienced it a bit worse by having the chain fall off.

Is this a poor design, not enough air in the rear shock, or too loose of a chainline, etc....?

Thoughts?
.nathan.

The first thing that comes to mind is your rear shock is not set up properly. If you are getting shock movement when you pedal then your shock is not set up right. I know it took me a good bit of time to get my rear shock dialed in. The second thing that comes to mind is your deraileur is not dialed in right. If you do not have that many miles on your bike then maybe it is time for a tune up to get rid of cable stretch and the like. I guess it could also be caused by to slack a chain but I am not real sure.
I am riding a 2003 nrs2 and have not had the problems you mention. Hope I helped a little bit

Jason

 

[tmo]

I feel your pain.

Sounds to like you are experiencing the notorious NRS ghost shifting. Basically, the seatstays flex, causing the rear der. cable to momentarily lose tension, causing the chain to shift to the smaller cogs. This problem is more common for larger riders and also more common in earlier models (2001, 2002). Do a search in this forum for ghost shifting and you will find loads of information about it. FYI, I also had that problem and fixed it by running full cable housing from the seatpost all the way to the rear der.

 

[RedRocker]

I've definitely heard about it but have not had the problem - and my RD has definitely been out of tune over the last year+. I have bumped into a guy who finally (I think) solved it with an XTR RD, I've also read very good things about SRAM RD's.
I weigh about 180 and ride an 03 NRS 2 with the stock XT RD and RaceFace crank.

 

[dgangi]

His is an '04

Sounds to like you are experiencing the notorious NRS ghost shifting. Basically, the seatstays flex, causing the rear der. cable to momentarily lose tension, causing the chain to shift to the smaller cogs. This problem is more common for larger riders and also more common in earlier models (2001, 2002). Do a search in this forum for ghost shifting and you will find loads of information about it. FYI, I also had that problem and fixed it by running full cable housing from the seatpost all the way to the rear der.

The '04 model years already have the design where the gear shift cable housing runs front to rear - no intermediate stops like the '03 and previous years.

This is actually the first I have heard anybody complain about ghost shifting on the '04 NRS. My NRS is an '03 and I have never had ghost shifting issues, even in the nasty rock gardens or under hard pedaling.

It is possible that you are having simple issues with your derailleur being out of adjustment. Derailleurs can be finicky little beasts when the cables stretch even just a small amount. Moving the barrel adjustment at the derailleur may be all that is needed.

Another possibility is that there is play in one of the joints causing flex in the frame. But given that the '04 NRS frames have sealed bearings all the way around, this is highly doubtful. But bearings can fail...so it's worth checking out.

I don't see how ghost shifting can be caused by an ill-adjusted shock. My NRS never ghost shifted, even when the shock was too low in psi.

In any event, take the bike to your local Giant dealer and ask for a tune-up. Tell them about your ghost shifting issues and see what they recommend. Good luck and let us know how you fix the problem.

Thx...Doug

 

[Gear Grinder!]

2 options that both work...plus one good bonus option...

The ghost-shifting was a major problem especially with the 02 and 03 models. Giant finally recognized that this problem was being caused by the flexion of the seatstays, which in turn slackens the cable and allows the rd to shift. Giant redesigned their '04 frame with stiffer seatstays. I suffered with this problem with my '02 frame until I finally found the solution after nearly 2 years.

Option 1: GOOD - The cable slackens between the two cable stops on the seat stay. Remedy this by running one continuous piece of housing from the top tube (nearest the seat tube) down to the rear derailleur. This way, when the seatstay flexes it will not affect the cable itself. You can even Dremmel out the stops and run the housing through them to make it all cleaner. I've used this on a few NRS frames, and the customers report a lot less problems.

Option 2: PERMANENT END TO PROBLEM - switch to a setup that uses an SRAM rear derailleur. It's not hype - this really works. The Shimano derailleurs take very little cable movement to shift the rd, such as the small amount that you get from seatstay flex. SRAM derailleurs take more cable movement to actuate a shift, so even with seatstay flex and a little slackening in the cable, the derraileur will stay put. No ghost-shifting...guaranteed. Every frame that I've switched to SRAM has reported perfect shifting, with no chain skip or ghost shifting at all. Problem solved.

Option 3: This one is good - since you already have an 04 frame this may not help, but hopefully it will help others with older frames and the notorious ghost-shifting problem. Giant, having recognized the ghost shifting problems, will replace older frames with current 04 models.

If money is a factor, go with the rerouting of the cable. If you've got some cash to spare, switch to SRAM. If you can go a couple of weeks without your bike, call Giant and get a brand new 04 frame.

 

[gatman]

cable to momentarily lose tension, causing the chain to shift to the smaller cogs

I have an '04 and I have experienced the same problem. Not too major, but just enough to notice and bug me.

That sounds great, but if my cable looses tension it should go up not down. But, it does go down?? So, it tells me that it gets tighter??

 

[Gear Grinder!]

Depends on derailleur---rapidrise or not

[/QUOTE]That sounds great, but if my cable looses tension it should go up not down. But, it does go down?? So, it tells me that it gets tighter??[/QUOTE]

I suppose this would depend on which type of derailleur setup you have. I had an XT that experienced the problems,and when the cable slackened a bit it jumped to a smaller cog. I suppose a Shimano Rapidrise rear derailleur, which works the other way, would shift to a largerer cog when it loosened. (cable tension moves a normal derailleur up to larger cogs, but moves a Rapidrise derailleur down to a smaller cog. Conversly, a slackening in the cable would move a regular derailleur down to a smaller cog, but would move a Rapidrise derailleur up to a larger cog. Confused? )

Either way, derailleurs only shift when the cable is pulled or released, and ghost-shifting can always be attributed to the cable somehow moving. The trick is to find the cause of the cable movement, and circumvent that. This is where SRAM does a great job...the amount of cable movement is not enough to let the derailleur shift, so nothing happens when the cable tension goes off by a bit.

 

[BreakingAway]

Giant will give me a new frame because of the ghost shifting?

Come on! I have a 2002 Nrs 2 and I have this problem.

So who do I contact to get my new Frame? I believe this when I see it

 

[Gear Grinder!]

Giant will replace the frame!!!

Giant will give me a new frame because of the ghost shifting?

Come on! I have a 2002 Nrs 2 and I have this problem.

So who do I contact to get my new Frame? I believe this when I see it

Giant will replace the frame because it is the cause of the constant ghost shifting. Contact the service/warranties department at either Giant Canada or Giant USA, whichever is applicable - they are both aware of the problem, and redesigned the frame to eliminate the problem.

My own frame was a '02 NRS 1, yellow and grey. This spring Giant Canada were incredibly helpful, and replaced the frame with a BEAUTIFUL blue '04 NRS1 - they shipped the frame to me first, and let me change over my parts before shipping back the old frame. Fantastic customer service, and very little down time!!!

The 04 frame has been redesigned with beefed up seatstays, and if you compare pictures of an 02 and an 04 you will see a very big difference in the rear triangle. It now works better for heavier riders. The 04 also comes with a Fox Float AVA rear shock, which makes the ride outstanding and is a world of difference over the SID rear shock that was spec'd on the 02 bikes. I have also heard of Giant replacing the frame with VT1's for some customers.

Many dealers are not aware of this problem, but the good dealers should be. Giant prefers that the dealer contact them on your behalf, but it worked best for me when I contacted them directly. The guys in the service dept were awesome to deal with.

 

[VaNRS2]

Giant will replace the frame because it is the cause of the constant ghost shifting. Contact the service/warranties department at either Giant Canada or Giant USA, whichever is applicable - they are both aware of the problem, and redesigned the frame to eliminate the problem.

My own frame was a '02 NRS 1, yellow and grey. This spring Giant Canada were incredibly helpful, and replaced the frame with a BEAUTIFUL blue '04 NRS1 - they shipped the frame to me first, and let me change over my parts before shipping back the old frame. Fantastic customer service, and very little down time!!!

The 04 frame has been redesigned with beefed up seatstays, and if you compare pictures of an 02 and an 04 you will see a very big difference in the rear triangle. It now works better for heavier riders. The 04 also comes with a Fox Float AVA rear shock, which makes the ride outstanding and is a world of difference over the SID rear shock that was spec'd on the 02 bikes. I have also heard of Giant replacing the frame with VT1's for some customers.

Many dealers are not aware of this problem, but the good dealers should be. Giant prefers that the dealer contact them on your behalf, but it worked best for me when I contacted them directly. The guys in the service dept were awesome to deal with.

So even if I am not having ghost shifting I can contact Giant and tell the mI am and they will send me out a new frame? I have an 03 by the way

 

[Knucklehead]

Giant will replace the frame because it is the cause of the constant ghost shifting. Contact the service/warranties department at either Giant Canada or Giant USA, whichever is applicable - they are both aware of the problem, and redesigned the frame to eliminate the problem.

Do you think they would replace a 2002 frame that has been WELL ridden? Really... it's pretty beat up. I've raced around 25 races on it, including 100 milers, 24 hour, 12 hour and 8 hour races. I've had to replace the pivot bearings twice, chainstay once. And the bottom side of the down tube and bb shell is nicked up all to hell. No dents or cracks though.

I never had the infamous ghost shifting problem before last week. I always used a Shimano XTR derailleur (non rapid-rise). But last week I replaced the old der with a new 2004 XTR rapid-ride der and now every time I stand up out of the saddle and really try to get moving, it constantly shifts up to an easier gear, shifting back once I sit down. It's soooo freakin' irritating.

Do you know how to contact their warranty department? The only info I could find on the Giant USA website was:

"
3587 Old Conejo Rd.
Newbury Park, CA 91320
California
USA

phone: For more info, please contact your local Giant
fax: authorized bicycle dealers.
"

Did you go through your LBS for the replacement?

Thanks!!!

 

[nathasm]

Voiding the Warranty

You generally have to go through your LBS when dealing with bike companies. Very rarely will they deal with an end user.

However, according to Gaint (and most others) warranty policy:

**snip**
THE ABOVE WARRANTY, OR ANY IMPLIED WARRANTY, DOES NOT COVER NORMAL WEAR AND TEAR. ALL WARRANTIES ARE VOID IF THE BICYCLE IS MODIFIED FROM ITS ORIGINAL CONDITION OR THE BICYCLE IS USED FOR OTHER THAN NORMAL ACTIVITIES, INCLUDING, BUT NOT LIMITED TO, FAILING TO FOLLOW THE OWNER'S MANUAL OR USING THE BICYCLE FOR COMMERCIAL ACTIVITIES OR IN COMPETITIVE EVENTS, INCLUDING BUT NOT LIMITED TO BICYCLE RACING, BICYCLE MOTOCROSS RACING, STUNT RIDING, RAMP JUMPING OR SIMILAR ACTIVITIES, AND TRAINING FOR SUCH ACTIVITIES OR EVENTS. GIANT MAKES NO OTHER WARRANTIES, EXPRESS OR IMPLIED
**snip**

So if you *SAY* you raced you void your warranty. In other words, you've never raced!
.nathan.

 

[Knucklehead]

Thanks nathasm!

I'm in good with my LBS. If the replacement is possible, I think we can work it out.

 

[upNdown]

This idea seems likely...

The first thing that comes to mind is your rear shock is not set up properly. If you are getting shock movement when you pedal then your shock is not set up right. I know it took me a good bit of time to get my rear shock dialed in. The second thing that comes to mind is your deraileur is not dialed in right. If you do not have that many miles on your bike then maybe it is time for a tune up to get rid of cable stretch and the like. I guess it could also be caused by to slack a chain but I am not real sure.
I am riding a 2003 nrs2 and have not had the problems you mention. Hope I helped a little bit

Jason

Check your shock; make sure you've got enough pressure for your weight. When I run my '01 NRS withough enough pressure, the derailleur seems to make a lot of noise when the shock compresses.

 

[mtbcyclist]

Oops wrong post (how the heck do you delete)

 

[mtbcyclist]

Holy cow! This rocks!

I have an 02 NRS 2 and have been having major problems with the shifting. I have even applied a fix to it and it still is a bit fubared sometimes.

Boy what a way to start a monday morning! LBS here I come!!