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Have Twinwalls? Please Read!!!
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Posted by: yz250roost

Hey guys,
I just wanted to warn all of you Renthal Twinwall users to check your bars as soon as possible. The Twinwalls seem to be cracking on the larger bar, right at the bend above the crossbar clamp, it will most likely on the side facing the rider. I have seen lots of these bars coming in over the last two months, and most of the cracks are very small hairline cracks that you wouldn't notice right away, you have to really examine the bar. If you find that your bar is cracking please send it to Renthal America as soon as possible for a replacement.
Jeff

Posted by: Casper250

I had that exact thing happen on the last set I had. Renthal replaced them for free! :thumb:

Posted by: yz250roost

Yep, Renthal is a great company. I hate to say it, but you might want to consider replacing them with fatbars, we keep having these bars coming back with cracks in them, I don't get any fatbars back, except for one pair from Ty Davis that looked like they had been through a nasty spill, and they didn't even break or crack, they just bent. I bought fatbars for my bike the other day.

Posted by: marcusgunby

roost im not so sure i would be happy with them just replacing them,on any product that has a significant failure rate they should issue a recall, i have heard of this problem for over a year and no one has ever published a recall as far as i know.Ive not heard of one snapping yet but it cant be a good thing to have crack in the outer bar.

Posted by: yz250roost

Marcus, I know exactly what you are talking about, I've seen some so bad that they have over a 1/2" gap between the pieces of torn metal, I too have not seen one that has been broken all the way through. If anyone has any questions about where to return them to or how to go about returning them, you can e-mail me or pm me. The easiest way is to get an RA Number issued from Renthal for replacement, that way they have knowledge of the product you are returning.]

And if you do send a pair in, send a little note to me with the bars saying you're from DRN.

Posted by: JTT

I've been hearing about numerous catastrophic failures of Renthal bars over in the Trials world too (these aren't Twinwalls, but standard Renthals). Seems like an odd coincidence. Have they changed suppliers, or alloys recently?

Posted by: TheJunkMan

hmmm. I better check the ones on my JTX maybe I will switch to the HEBO's

Posted by: kawdude

Interesting. I have two sets of twinwall bars both ended their lives with the problem mentioned.

The first time, the bike fell over and the bar end darn near broke off. I couldn't believe it and I kept thinking about how strong these bars are supposed to be. I had a hard time replacing this because sales person felt that I had laid it down or hit a tree...something greater than the bike falling over. :flame:

The second time the crack was found by accident which made me think that it was the issue the first time. In talking with Renthal I brought up the previous issue and at this point they agreed that the bar was probably cracked before the bike fell...duh!

Either way I'm done with the twinwall bars until these issues are fixed.

TAG bars all the way :thumb:

Posted by: roadrash1

Years ago, didn't McGrath DNF a supercross race after the prototype for these bars broke on his bike in a low-speed tip-over?

Posted by: mxneagle

Actually I thought MC DNF'd because the bars were too strong and actually broke the triple clamp instead.

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Posted by: Okiewan

test2

Posted by: Okiewan

test3

Posted by: Okiewan

test4

Posted by: Okiewan

sorry!

Posted by: roadrash1

I think you have it right. I just remembered it was one of the initial runs of the big bars.

Quote:

Originally Posted by mxneagle

Actually I thought MC DNF'd because the bars were too strong and actually broke the triple clamp instead.

Posted by: Jeff Howe

I cracked 3 of them like this, first one occured in late 2000 and then 2 more in 01. I got tired of sending them back even though they were replaced for free. Moved to Azonic Double Cross in 02 and haven't had a single problem in 2 years with them. I gave away the last one that cracked and the guy got new bars out of them of course. I personally think they are junk and I'll not buy another as long as I ride.

MC snapped the mounting bolts on his bar mounts in that race, not the bars.

Posted by: will pattison

well, i may be biased, but i think the answer to all renthal problems is to switch to pro tapers!! ;-)

as for tags, well, here's an inside story...but to keep the guilty parties safe, i'll try to keep it anonymous.

recently, a certain well respected and very fast pro rider recently joined a new team. his old team had a relationship with renthal, and this rider chose to continue using them even though his new team has a relationship with tag. this rider's new team also has another member that's been on the team a while. that rider as well as a rider who used to be on the team but who is now on a new one have always used pro tapers in spite of that same relationship with tag. confused yet? in other words, not all was as appeared on the surface - both riders on that team preferred pro tapers.

well, the unamed new rider took a header at a recent supercross and bent his renthals. now, that rider's new team is the beneficiary of technology from one of the o.e.m. racing departments, but is itself not a factory team. the o.e.m. factory team has had a long standing relationship with pro taper, and it was recently learned that said o.e.m. racing department called the owner of said satellite team and basically "suggested" that they run pro tapers from now on.

now, all credit where due - there are lots of good bars out there, but i think that was about as clear a message of confidence in the quality of pro taper as you could ask for.

and yes, i would swear in court as to the truth of this story.

wp.

Posted by: Jeff Howe

I am one of them weird old school guys that HAS to have a crossbar! I'm sticking to Azonic's. Bars just don't seem right to me without a crossbar.

Posted by: Senior KX Rider

I agree. I have a set of ProTapers and a set of Tags hanging on the wall but I feel more comfortable with the crossbar.

Posted by: fastoneyz426

I had the same problem on my sons bike. The whole right side came loose and he came in the pit and we duct taped it to the bark buster to finish the race. I just thought that he hit something real hard in the woods. When I took the tape off the throttle side slid right out of the outer bar and just left the plastic tube showing.

Posted by: KXaggerator

I had a high speed get off in the desert on my KX500 that bent one bolt and sheared the other off of my Applied bar clamp, but I still run those same Protapers five years later with no apparent damage to them. Now if they would just make a Jimmy Button bend I would be even happier.

Posted by: will pattison

Quote:

Originally Posted by KXaggerator

I had a high speed get off in the desert on my KX500 that bent one bolt and sheared the other off of my Applied bar clamp, but I still run those same Protapers five years later with no apparent damage to them. Now if they would just make a Jimmy Button bend I would be even happier.

jimmy button, eh? you must be 7' tall!

if you get me the specs, i can tell you which pro taper is the closest.

also, for you crossbar guys, be on the lookout for the new pro taper se bar. it's our new 7/8" deluxe, and it's phat! i think you can even see it now over at www.protaper.com. we basically went after all the weakness of current products and tried to make a top of the line 7/8" product that addressed them all. this bar is stout! we also offer 7/8" bar mounts for our entire line of triple clamps.

wp.

Posted by: KXaggerator

Will,
I am just over 6', but I am tall in the torso. I have the Button 7/8" Renthal on my KX310 and nothing feels better on any bike I have ridden and the cross bar just clears my GPR steering stabilizer. Here is the goon like specs:

A - 807
B - 110
C - 85
D - 205
E - 67

Posted by: grass-digger

i dont believe that i will ever go withought my pro-tapers, i have a set on my cr250 and there 3 years old still as strait as when i got them, that is after bending my triple clamp bolts about 30degrees

, My tag bars on the other hand bent my first crash and i had to get a new set of pro-tapers for my crf450

Posted by: will pattison

Quote:

Originally Posted by KXaggerator

Will,
I am just over 6', but I am tall in the torso. I have the Button 7/8" Renthal on my KX310 and nothing feels better on any bike I have ridden and the cross bar just clears my GPR steering stabilizer. Here is the goon like specs:

A - 807
B - 110
C - 85
D - 205
E - 67

well, we can get close. the new se bar has a kx high model that is 813 wide, 108 tall, but has more sweep - 78mm. i don't know if the extra sweep would be an issue or not, because bend is such a personal thing. let me know if you have more questions!

wp.

Posted by: sampson

yes it was the triple clamp that broke

Posted by: BlazinBoy

Fellas I work at a cycle shop here in Cinci which supports alot of motocross/offroad racers and I NEVER recommend the twinwalls to anybody. The problem is they are TOO stiff! Instead of flexing when needed they simply snap or crack. Regular Renthals are a great bar (for you crossbar types) and the Renthal Fatbar is excellent also. Stay away from the twinwalls! They suck and are not worth the rediculous price they are. Pro Tapers are the best fatbars out there. Tags are good but I always recommend the Pro-Tapers. I personally use the Renthal Fatbar (sponsorship and preferred bend) and love it but have a set of Pro Tapers on my 97 KX. Nice to see Pro-Taper is making a high KX bend. That is what my Fatbar is. Awesome!

Posted by: Daisycutter

I've got a set of Twinwall's on my CR500. They've been on there for a year now and been in contact with the ground a few times. Including my collarbone breaking 65mph wheelie into a mesquite tree incident that buried the throttle side of my handlebars 6" deep into the dirt 5 weeks ago.

I have yet to see any cracks. What's the failure mode? Low cycle fatigue?Catastrophic failure implies that the bars completely separated causing much added damage or injury.

Posted by: SND

Quote:

Originally Posted by yz250roost

Hey guys,
I just wanted to warn all of you Renthal Twinwall users to check your bars as soon as possible. The Twinwalls seem to be cracking on the larger bar, right at the bend above the crossbar clamp, it will most likely on the side facing the rider. I have seen lots of these bars coming in over the last two months, and most of the cracks are very small hairline cracks that you wouldn't notice right away, you have to really examine the bar. If you find that your bar is cracking please send it to Renthal America as soon as possible for a replacement.
Jeff

Hey guys, Shawn Norfolk from Renthal here. I got wind of this thread, so I came right over.

Here's the skinny on the Twinwalls. The Twinwall came out in 1998. The bars that were produced PRIOR to 2002, had the problem of which you speak. Having said that, let me explain. It is a very simple problem and a very simple solution. Understand that even the bars that developed cracks were not deemed 'unsafe'. I know, I know...that sounds ridiculous, but allow me to explain further. The strenght of the Twinwall comes from the inner wall (a standard Renthal bar) that is surrounded (like a suit of armour) by the outter tube. The outter tube developed a crack because the balls that we used in the peening process were too large. As they put the compressive load on the outter surface, they thinned the material and the cracks would develop. Now, it didn't happen to all of the bars...just a few (probably 130-150 bars total out of the more than 100,000 that have been produced. Also, it only occurs in the area between the crossbrace clamp and the end of the outter tube. Why? This is where the material steps down from 1 1/8" to 1". That particular part of the handlebar is the thinnest part of the outter tube. NOT of the bar itself (as a whole) just of the otter wall. Now...You may ask yourself...How can a cracked bar be safe?

Here you go. On the Twinwall, the outter tube acts as an exoskeleton. It is made to take all of the abuse from the clamps, rocks, tie downs etc. All of these things abuse aluminum. The Twinwall is not going to have a fatigue failure (the number 1 cause of broken bars...with #2 being crashes). This simple fact makes it the safest bar in the world. The outter wall can be cut, cracked, notched etc...all the while the inner tube remains 100% perfect and as strong as it ever was. This is why no recall was done. The bar was not a safety issue. Had it been...we would have recalled them. We would NEVER put our customers at risk.

Now, How can you tell if your Twinwall was made prior to 2002?

simple. On the bars, between the clamps, there is a series of numbers. If it is not between the barmount/clamp area...it is out on the left grip end of the bar. The numbers look as follows:

918 59401801.

the FIFTH number (the 9 in this case) is the number that you need to look for. Your bar will either have a 9 or a 6. 6 was made before 2002, and 9 was made after 2002. Please understand again that just because you don't have a (9) bar...doesn't mean that your bar will crack. Again, only 1% of the bars developed cracks. However, if you crack your bar, send it to us and we will replace it.

The TwinWall is the strongest and the safest bar that is available. THAT is why all of our team riders use this bar. It is stronger, safer, less likely to bend, and more likely to make it through a crash. I hope that this makes it easier to understand for you guys/gals.

Posted by: Jeff Howe

In this instance I will withdraw my comment of not ever buying Renthal TwinWall bars again. Although I had 3 of them crack I never had a problem with them beyond that. I didn't know that the crack was no big deal, but I can say that after noticing the crack on my 3rd bar I rode most of the rest of the season with it as it was.

I felt I would never be able to destroy my Azonic DoubleCross bars. I did it last Thursday at Cooperland though

. I need to order new bars now and after riding a 04 KX 250 I seem to really like that stock KX bend. What I need to know is if KX bend bars are the same as 04 spec??

Posted by: SND

Quote:

Originally Posted by Shocknut

In this instance I will withdraw my comment of not ever buying Renthal TwinWall bars again. Although I had 3 of them crack I never had a problem with them beyond that. I didn't know that the crack was no big deal, but I can say that after noticing the crack on my 3rd bar I rode most of the rest of the season with it as it was.

I felt I would never be able to destroy my Azonic DoubleCross bars. I did it last Thursday at Cooperland though

. I need to order new bars now and after riding a 04 KX 250 I seem to really like that stock KX bend. What I need to know is if KX bend bars are the same as 04 spec??

The stock KX bend is actually a bend that they borrowed from us. It is our standard 983 bend...which is a 996 TWINWALL bend. It is the old Emig/Bradshaw bend!

Posted by: Jeff Howe

Thank you for that info Mr Norfolk. I think that bend with some slightly higher mounts will suit me well.

Posted by: KawieKX125

Thanks for clearing that up! I had one of the early sets of twinwalls and they cracked and you [renthal] replaced them no questions asked with a bend of my choice. Thanks again!

Posted by: BlazinBoy

Shawn thanks for the info and I will definately inform my customers. Sorry to be so hard on the twinwalls......all of your other porducts are excellent!

Posted by: cernicsRM125rider

DO they replace them if they were made before 02 and there bent really badly???

Posted by: Jeff Howe

Only if they came that way from the factory.

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Have Twinwalls? Please Read!!!

This is the text version of DirtRider.Net Click Here for the Full Version

This is the text version of DirtRider.Net
Click Here for the Full Version

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