Near Lethal Product Failure on Grubee GT1

[Irish John]

ATTENTION ALL OWNERS OF GRUBEE GT CRUISERS
Today on the busy Pacific Highway in far northern NSW a 3 week old Grubee GT1 cruiser suffered catastrophic failure in the steering head nearly causing the death of my customer who got the GT1 & G4 Grubee kit that I reported on elsewhere.
The alloy that is inside the steering head tube completely fractured and the only way the rider maintained some steering ability was by pressing the failed tube downwards to get some purchase between the broken parts. The only thing stopping the handlebars from falling right off was the head bolt that was allowed the rider to get a little steerage to avoid veering head on into oncoming traffic. The attached photos show what snapped. I reckon this is so serious that the authorities will probably demand a total product recall.
This is on top of the 11T freewheel failure after 120 kms and the new 11T will fail at the same mileage because it cannot withstand the forces that the gearbox applies to it. I think this justifies my frequent complaints about dangerous quality fade and attrocious quality control. The rider is ropeable with anger and wanted to fly down to Sydney and see the wholesaler but the wholesaler has just left for Thailand.
Suffice to say I was totally justified in bagging this whole product package. I hope you are reading this Biketec because the crystalline alloy in the sheered tube clearly tells us that the problem is unsafe weak alloy mixes being used on applications that absolutely demand quality control. The whole head design is a fatality waiting to happen and blame will need to be laid squarely at the feet of the manufacturer. I stated in another thread appraising the GT1 that I didn't like it because it was pokey and had no fenders but that it is probably OK for someone who can't afford a decent cruiser bicycle. I will stick with the one piece Schwinn quill stem & head because they are made to the required strength and that's important when your life depends on it. I am very angry at what nearly happened to my friend and customer and I think it is justified. It really emphasises the folly of using cheap shonky bikes and this GT1 has a very very serious problem to be resolved. Personally I don't see any option other than a total product recall.

 

[augidog]

enuff with the "race card" already!!!

if it's junk and it came from china, it's chinese junk. period.

i have plenty of quality chinese components on my MB, so we know it can be done. this specific issue is appalling...for want of a solid stem that costs the maker maybe a buck more, the maker would risk the lives of it's customers. that this kind of stuff happens at a rate way-above-average in china can't be ignored as significant.

i don't think any of us here blame the chinese workingman...i've never heard that from anyone...while it may be (at times) about economics & (shudder) politics, this is NOT about culture, it's consumers sharing info about products and sources. imo, the same opinion i've had all along, there's only one global-group what can fix this...the consumer.

period.

 

[Irish John]

Dealer vs. Dealer
Only one is right.

If Irish John broke the steering himself to trash Grubee, then thats a major fraud.

If Irish John didn't break the steering himself, then arceeguy is making false accusations.

One of these two dealers is a fraudster. Which one?

Thanks Skyl4ark you are right. One of us must be a downright liar but I am not a dealer. I build bikes for people after letting them choose the components - the only frame-mount GB I can use is a Grubee mark 2 - which I have to buy retail, Then I offer whatever cruiser they choose but I won't go below a Schwinn mid-range quality which I also buy retail. I will advise about the problems of using an Electra or a Felt etc but the choice is entirely theirs. One-offs are going to cost more obviously. I was offered Micargi cruisers wholesale but I can't use them because close inspection showed me the quality wasn't good enough and if I tried using them they;d explode in my face and I'd be in strife. That's how I got to know about the springer forks with V-brake bosses and I was prepared to get them for MBc members at cost price only but the cost price would be Aus $50 plus freight which is probably too much. I wouldn't have made anything and that was OK by me.
I might become able to get bikes and Honda engines wholesale but that will just make my bikes cheaper. My labour rate often works out at $10 an hour which is half the minimum wage because it takes a long time to build tem well.
If I'm using some special bike like an Electra it becomes more expensive cos of the time factor and I might only break even. This year I can only offer the Schwinn D7 cos the others are discontinued but the only GBs in stock at Grubee dealership is the G4 and I certainly won't be offering that. When my few remaining old Grubee GBs run out I'll be unable to build any bike unless they ask for a Staton rear mount. I was pleased about the GT1 cos I thought it may have been OK for my purposes and I could use it to replace the discontinued cheaper Schwinns but now I see I can't so I suppose this impacts heavily on what I do for a bit of money. There are other guys offering ZBox HTs on KMart and BigW bikes around here for $800 but I only see the ones people bring to me for help. I can't help them but I tell them that $800 is a lot to pay for something that packed in after 10 days to the point of being not worth fixing. That $800 doesn't include tipping fees of $35 at the local council tip which is where those bikes will end up. It is sad because motored bikes really do offer a great alternative to the use of cars but the quality of so much of the industry means that they will probably be banned from use on public roads mainly for safety reasons. I suppose that the focus on price at the expense of all else (even safety) has ensured their own demise. It's like digging your own grave.
But I ain't a dealer - I just sell a finished product and a 12 month unlimited warranty means unlimited. A limited warranty usually isn't worth the paper its written on. A 30 day warranty is useless on a product like this when you stop and think about it. In all fairness the Grubee dealer offered me I think it was a 4 month warranty on the 2-stroke kits and I appreciated that because I wouldn't be prepared to be that generous but I like the guy and I know that if I use those kits I'll still be up for shipment and labour costs to replace them.
I don't want to sell anything that has people banging angrily on my door. I want a quality product at a fair price and I think that makes sense.
I can't offer a quality product when my current supplies run out so I'll have to find another hobby that pays. I reckon there's some scope left in Ladies bikes with Staton or Gebe according to price range. Ladies make up 50% of the population but they'd have to be pretty bulletproof for the ladies.

 

[Just_Gasit]

I think we all know about the kind of quality that ships out of China. Some things are better than others and some actually is pure junk. Some things are a mix of the two.

As for the gooseneck / steering head or what ever name you go by, I don't see how it could have broken at that point if the bolt going THROUGH it was in place and tight? If the bolt came loose... yes. However, the picture posted would require the bolt to be very loose at the time of failure and wouldn't it start slipping in the head set assembly by then? There is no mention in this OP about the condition of the gooseneck bolt. I'm sure anyone that has worked on a bike would understand what I am talking about once they look at the picture again and think about how it functions and how important the long bolt that passes through it is. Furthermore, I think that part could crack and EVENTUALLY cause a control problem but it would feel loose by then as well. I see no sign that the part was slipping in the area of the break as there are sharp "teeth" of broken alloy that surely would have prevented slippage if the bolt was still somewhat secure. This photo fails to convince me of a failure with loss of control. I am not taking sides by the way, I am calling this as I see it in the photo.

 

[augidog]

technically speaking...

assuming i'm seeing this correctly:
2 separate pieces of hollow tubing coupled with a "plug" of cast alloy is ridiculous for such a crucial component, considering that suitable options are available. or, maybe it would be fine if someone hadn't cheaped-out on materials. from john's story and the pics, it seems to me that if the bolt hadn't been sufficiently tight this would be a story of grave injury or perhaps even death.

edit:

to be absolutely scientific (and fair) about this, we have to ask other owners for an inspection and pictures.

hey there, John...plenty of men get around just fine on GEBE's, too

 

[Irish John]

assuming i'm seeing this correctly:
2 separate pieces of hollow tubing coupled with a "plug" of cast alloy is ridiculous for such a crucial component, considering that suitable options are available. or, maybe it would be fine if someone hadn't cheaped-out on materials. from john's story and the pics, it seems to me that if the bolt hadn't been sufficiently tight this would be a story of grave injury or perhaps even death.

edit:

to be absolutely scientific (and fair) about this, we have to ask other owners for an inspection and pictures.

hey there, John...plenty of men get around just fine on GEBE's, too
View attachment 21171

Thanks Augidog. You are dead right in all you say. The owner, Sean, who owns this bike will respond soon with pictures of what happened and of the dismantled stem, expander bolt and wedge. He is really mechanical and seems to know a lot about these matters so I look forward to reading what he has to say.
The attached picture shows a typical orthodox stem. This GT1 stem is totally unorthodox and uses an alloy plug as a splint to join the two sections of tubing. The hole in the middle is not even threaded and the expander bolt drops through a large hole in the middle of the alloy splint. I forget what the wedge that holds the stem in place is like but it will be a typical wedge. I don't think it is a dogged wedge like the one in the picture but the principle will be the same. To join a vital component in this way is downright negligent to the point of being culpable and I really think this affair is not going to end simply unless the stem is immediately replaced on all current bikes but between now and then there could be a fatality. I installed the stem from the boxed bicyle and I tightened it to the point where the handlebars can turn if you stand in front of the bike holding the handlebars and twisting them while keeping the front tyre tightly clamped between my legs. That is the way I was always told to tighten a stem so that in the even of impact the bars willl twist before bending. That's what happened when I hit the school bus recently and the bars took the inpact. Sean says that the bars were not loose before the fracture - if the stem was loose you would immediately know about it for obvious resons I don't have to explain. Nor were they overtightened. The alloy plug simply fractured suddenly and catastrophically without warning leaving Sean with no steering. The bolt did not fracture. I don't think I know if the wedge fractured but Sean will post his story later tonight because he is disgusted at what Arceeguy has been implying to the point of being too angry to respond. We will get to see the expander bolt, wedge and stem close up later but I think Sean's pictures of the veins of impurities running through the alloy and visible to the naked eye will convince most people that what has happened here is a botched attempt to fabricate a cheaper stem has been undertaken either by incompetent people in a totally unorthodox manner that is indeed life threatening. As most users know there is really no force being applied to a cruiser's handle bars because of the upright sitting position. You are not leaning over the bars with the weight of your head and top torso being transfered to the front like on a road or mountain bike. That might be why they thought the alloy plug splint would do the job - "she'll be right mate" attitude has really come unstuck this time and this matter can't be swept under the carpet.
I suppose Arceeguy could say that I secretly injected impurities into the alloy when the plug splints were being made in China but even that doesn't explain the use of a dangerous and inappropriate use of a plug splint to join two bits of stem tube. Unless I designed it that way myself disguised as a Grubee engineer entering China under a false passport and working my way slowly up the Grubbe ladder of command so I could perform such an evil act. I don't think Sean the victim will buy that story but I'll try him and see if it works!

 

[Irish John]

I think we all know about the kind of quality that ships out of China. Some things are better than others and some actually is pure junk. Some things are a mix of the two.

As for the gooseneck / steering head or what ever name you go by, I don't see how it could have broken at that point if the bolt going THROUGH it was in place and tight? If the bolt came loose... yes. However, the picture posted would require the bolt to be very loose at the time of failure and wouldn't it start slipping in the head set assembly by then? There is no mention in this OP about the condition of the gooseneck bolt. I'm sure anyone that has worked on a bike would understand what I am talking about once they look at the picture again and think about how it functions and how important the long bolt that passes through it is. Furthermore, I think that part could crack and EVENTUALLY cause a control problem but it would feel loose by then as well. I see no sign that the part was slipping in the area of the break as there are sharp "teeth" of broken alloy that surely would have prevented slippage if the bolt was still somewhat secure. This photo fails to convince me of a failure with loss of control. I am not taking sides by the way, I am calling this as I see it in the photo.

A few points need to be stated here. The bolt is not connected to the alloy plug in any way - it drops clear through the middle of the plug without touching the sides. If the bolt is tight as it has to be then the only thing holding the two pieces of stem tube together is that alloy plug acting like an internal splint. Any lateral force on stem will be tranferred directly to the alloy plug. The expander bolt simply pulls the wedge up to force the split bottom of the stem tube against inside of the fork tube and stop it rotating in the fork tube. When the plug fractures like it did the only steering you will get is from a now loose expander bolt and that is practically no steerage but the bolt stops the handlebars from dropping right off until the brake cables come into play about halfway to the ground. What Sean had to do quick smart was press the top piece of the stem onto the bottom piece and use the crystalline roughness of the alloys fractured surfaces to get some turning moment applied.
I think the pictures actually explain that. The problem is the alloy plug splint was never an acceptable method for jointing two piece of tube that are a critical structural component in the steering system. The splint takes the lateral forces from the point where the stem exits the head, The bolt has no structural integrity in the system except to pul the wedge up and splay out the stem tube to stop it turning inside the fork tube, The expander bolt would apply some downward force to sandwich the two stem tubes together but that is never going to give any serious bonding between these two tubes - the alloy splint is the structural load bearer and it is a terrible method to joint two tubes by any reckoning.
As for the comment about other owners needing to post their experience of this model of bike so we can evaluate the problem, I am not aware of anyone in MBc owning this new model yet which is why I posted that other thread evaluating the bike in the first place. I know what the supplier has told me but it cannot be believed - his explanation about the freewheel problem is we are the only ones who have complained but we are the only ones who have tested the bike so how could there be any other reports. Re the current stem failure the supplier is overseas but he's not an idiot and he'll know what the ramifications of this stem issue could mean for him. He'll be straight on to Grubee if he isn't onto him already. The freewheel problem is systemic and won't go away either but it won't kill people.

 

[fetor56]

GT1A Beta.

 

[JemmaUK]

Im no metallurgist but neither am I blind...

It doesnt matter if someone rails on about a bad product from a matter of bias or anything else... If I had bought that product and that was what was holding the controls together - lets face it everything on these bikes is controlled from the bars - then I would feel perfectly justified in demanding both my money back and a safety recall..

That joint is cheaply made and it shows crystalline fracture - which will tell you two things - one, its inherantly dangerous - two, that the failure is stress related since its a similar pattern to that shown by aircraft parts that have failed due to excess stress.. It wouldnt look like that if someone had taken a hammer to it.

Indeed, if anyone remembers the cross america story - the guy who did that had exactly the same problem with metals crystallising under long term stress.

Back to my earlier point ... many americans will remember ralph 'convair' nader... he of the whining about rear engined cars amongst other things. He was perfectly correct - engine hung ***-out behind the rear axle means skittish handling but ONLY and this is the important part, only if you drive it like a nutcase... Hitler, of much beloved memory (sarcasm alert), actually penned an order denying his officers permission to drive the tatra T77, 77a and later T87 because they killed more officers in road crashes than the entire czech underground managed!

My point is this - if someone makes a fuss about a supplier or manufacturer for no reason then that is one thing - but when there is a catastrophic failure of that product which may be common to other copies or versions of that product then people need to be made aware and the problem dealt with.

What people here seem to have missed totally is that fact that this is another stick we can be beaten with over the safety or otherwise of MBs - and dont we just need another excuse for the authorities to have their way? yeah.. I thought not.

Just looking at the joint on that machine should tell anyone its not fit for purpose - my grandmother could have done a better job of it and shes been passed away these last 4 years. Now, it might not be Grubees fault, that has not been proven since they are likely to buy in parts like most other companies... but its happened, may happen again with worse consequences and has to be addressed as soon as possible.

 

[customcruiser]

im not one to fight....but just thought id have a say it is a forum after all

1.without china everything would be non existent thisforum wouldnt exist we wouldnt have computers mass produced (even tho the computer was invented by a *** german apple logo no the san francisco pride colours)

2.i own a zbox 66cc frame mount and have done over 1500km on it ith it only ever majorly broken down once it was really my fault (rode it 70km non stop and the magneto blew)

3.im not saying one thing is better than the other but my point is nothing is meant to last forever......wat i do if things break i fix them and make them stronger and if its broken beyond its original use it gets recycled into something fun


adam.

 

[Irish John]

Adam, can you remember Windows 3.1? It worked quite ok but couldn't multi task. Well those computers weren't made in China. None of that stuff was made there at that time. Can you remember when hard drives almost never broke down?
I'd love to see you tell my friend that "nothing is meant to last forever"
"Hey, what's all the fuss about?" I'd even pay your dental and medical bills when you came out of unconsciousness after telling him that.