Caution! Fenders are Death!

[Citi-sporter]

The only problem here is the lack checking and double-checking your fasteners for the fenders.

Buy a tube of LockTite blue when you buy that engine and take the time to go over all the potential bits that might loosen on the bike itself, before you put that engine on. Check that there is sufficient clearances for the tire and any stray debris it might pick up between the fender and the tire. LockTite and torque all small fasteners.

 

[mason_man]

Sorry to hear Shaggz, lots of good advice here.
Sometime its pick your poison.
Do what's best for you.

Ray

 

[Dan]

Thats good advice, Cti.

But the main problem with fenders are not that the fasteners loosen, but that the brackets themselves fail and let go. Often with the nuts, bolts, rivets still secured to them.

Very often it is just an L bracket that is just bent. That causes a weak spot at the outside of the bend. So with the vibrations, it wiggles it self to death.

The only problem here is the lack checking and double-checking your fasteners for the fenders.

Buy a tube of LockTite blue when you buy that engine and take the time to go over all the potential bits that might loosen on the bike itself, before you put that engine on. Check that there is sufficient clearances for the tire and any stray debris it might pick up between the fender and the tire. LockTite and torque all small fasteners.

 

[Dan]

Just found pics of what I mean;

http://motorbicycling.com/showpost.php?p=99638&postcount=12

That bike had awesome fenders. Think Tom ended up with em?

 

[2door]

Good advice but not fool-proof.

I'm not beginner and have a lot of years behind me with mechanical stuff. I was certain the fender couldn't come loose, get tangled or fail yet, it did. As Dan said the fasteners didn't fail but the steel fender itself was ripped out of the mounts and wrapped itself around my rear tire. Also mine wasn't a case of neglect. Six miles before my accident I had gone over the bike checking for possible weak points because it was a new bike. The fenders felt secure and all fasteners were tight and in place. I was never really able to determine exactly what happened, or more accurately, how it happened. But it did.

I still run fenders but they are all bobbed and mounted in such a way that they can't rotate down and under the tire. The fender that failed and caused my crash is half the length it was before the accident and welded to the mounts. And believe me, it gets checked before every ride and even during a ride. So far, so good.

Tom

 

[Dan]

Same thing, here. Fender looked great. No visible stress and just let go.

Way I secure them now is 2 ubolts and drill 4 holes in the fender. Ugly as sin but holds em.

Still kinda gun shy. Really dang hurt and first thing I thought as my face was bouncing back up was that Carol would end up spoon feeding me.

So dang glad you guys had talked me into wearing a helmet. Or that could have been the outcome.

And I wasn't going that fast.

 

[maniac57]

My big issue with fenders is the danger of failure WITH NO WARNING SIGNS.
The high-frequency vibration put out by these buzzy two strokes is simply too much for almost ANY fender mounting I have seen.
You reinforce everything and it's STILL a risk.
My skin is more important than looks.
Just my opinion.

 

[scotto-]

Fenders.........who needs them? You won't find them on any of the bikes I've built in the past five years. They are the first things removed along with the chain guard, right after the reflectors

 

[SpecializedMountainMoto]

Who cares about the fenders? Just a symptom.

I would be more worried about the frame crack.

Both frame cracks. The fender support cracked off and the frame cracked.

Bolt a POS pot metal engine onna bike and take your chances. The life you have to lose is your own. Really think about it.

All you guys always complain about those spandexers doing 30 on their bikes and you can't go that fast by law. They have zero vibration pedal power bikes that cost a grand or more and are fit. You have a $100 bike with a $150 vibration machine lashed to it and you are not fit enough to pedal at 30 mph.

Bicycles are not designed to be equipped with gasoline engines. You take the risk. Is it worth it?

Wow, POS engine kit... I think your on the wrong forum Bud

 

[oldtimer54]

Wow, POS engine kit... I think your on the wrong forum Bud

That's what I was thinking. (every forum has at least one?)

 

[Shaggz]

The only problem here is the lack checking and double-checking your fasteners for the fenders.

Buy a tube of LockTite blue when you buy that engine and take the time to go over all the potential bits that might loosen on the bike itself, before you put that engine on. Check that there is sufficient clearances for the tire and any stray debris it might pick up between the fender and the tire. LockTite and torque all small fasteners.

its not that i didnt check them the bracket on the fender broke there was nothing i could have checked to know that was going to go down

 

[oldtimer54]

Who cares about the fenders? Just a symptom.

I would be more worried about the frame crack.

Both frame cracks. The fender support cracked off and the frame cracked.

Bolt a POS pot metal engine onna bike and take your chances. The life you have to lose is your own. Really think about it.

All you guys always complain about those spandexers doing 30 on their bikes and you can't go that fast by law. They have zero vibration pedal power bikes that cost a grand or more and are fit. You have a $100 bike with a $150 vibration machine lashed to it and you are not fit enough to pedal at 30 mph.

Bicycles are not designed to be equipped with gasoline engines. You take the risk. Is it worth it?

We ALL complain about spandexers doing 30? I don't remember doing that? (Iam getting old through so anything is possible?) Where not fit to pedal 30? How do you know??? Have you been spying on me? (I hate it when that happens!!) Do you have any thing good to say here or are you jest messing with us lol? Seems to this one you come here to mess with people doing the very thing the forum was made for building bikes with engines mounted in them?? This I don't get? (but I have been told Iam slow some times)
This is a engine + bike forum. That's what it was made for. We ALL take the risk that's why where here. Why are YOU HERE? Is it worth it? (LMAO)

 

[biknut]

One thing everyone needs to realize is this has happened many, many times to even the most experienced of riders, and builders. Tom is a good example, but certainly not the only one by any means. Just because it hasn't happened to you, don't get on a high horse, like you're smarter than everyone else, because the truth is, you've just been lucky.

Vibration is the common denominator. Not where the bike came from, not the price of the bike, not poor workmanship, not negligence on the riders part.

 

[crassius]

front fenders always fall off the chinese schwinns & huffys - what one does is take a standard gas tank bracket, cut it in half right in the middle of the curve, press the curve flat to form a right angle bend, then shove the end thru the slot in the fender where the original fender bracket went thru - the metal in the gas tank bracket is strong enough to hold that fender even if it just hangs there without a bolt thru it

 

[KCvale]

Bummer Shaggz, hope you recover soon.

I find 3 point mount fenders to nothing but frame holes not the axle to work very well.

That means the middle L bracket frame mount, and then two sets of struts to separate frame holes.

What that does is not give the fender mounts a center pivot point so they tend to stop themselves trying to bend against other stops and each other if the L breaks.

About half my builds (2-stroke, 4-stroke & electrics) have full fenders and we just reinforce the top bracket L slots and all the strut bolts with some JB and no failures I know of yet.

I like fenders and chain guards here in the desert. There are a myriad or things the 'road' can toss in your face or down your back here I'd just as soon keep on the ground.

Maybe it's just the 2-stroke engines I buy or the way I build, but vibrations aren't any worse than a 4-stroke and minimal enough that they don't shake themselves apart.

 

[Mike B]

I am in the right place me thinks, a DIY motorized bike forum right?

I have 5 motorized bikes;

(1) happy time on a wallmart OP Roller
(2) Magic Pie electrics
(2) Staton friction drives, one with a Robin-Subaru and one with a Tanaka

The happy time although it has no fenders cracked the chain guard tab, broke the rear grade 8 socket head cap screw motor mounts and vibrated the air cleaner and the muffler cap off into the road. The motor mount issue caused me to push the bike home.

The other 4 bikes have suffered no problems of this nature because they do not vibrate so bad. Zero in the case of the electrics and very little in the case of the friction drives. Maitainence is like a pedal bike, just squeeze the tires to check pressure and go.

Motorized bikes are a lot broader than Chinese frame mounted 2 stokes. I know, I have one. And that will be the only one I will ever have. Compared to the other 4 it is an unreliable POS that I am unwilling to risk my life on. Please do and ride anything you want, it's your choice.

 

[biknut]

Maybe it's just the 2-stroke engines I buy or the way I build, but vibrations aren't any worse than a 4-stroke and minimal enough that they don't shake themselves apart.

Let me have one, and I'll teach you how to break it lol.

 

[wheelbender6]

I think a few of you misunderstood Mike B. I took his remarks as, "If the spandex guys don't trust a bargain bike for pedaling at 30mph, then a motorized biker shouldn't trust a bargain bike for motorizing and travelling at 30mph".
-I think you can motorize and travel safely at 30mph on a bargain bike if you don't have one of those frames with the cargo rack welded to the seat stays. I think you also must more closely watch your adjustments and bolt tightening on a bargain bike, but it can be done safely.
-I still have one foot in the spandex world. I won't do another MS150 but I still do shorter charity rides.
The spandex guys' bike must be comfortable for him/her to spend all those miles in the saddle and making a 20lbs bike comfortable enough for a five hour ride isn't cheap.

 

[Hawaiikelly]

So many things can happen quickly. Fenders do a lot of good things, they just really need to be attached very strongly. In many places they are required to make the bike legal. They are just one more thing to look at before you take a ride. After reading more than one post about them, they are on my watch list!

 

[mason_man]

Ok Shaggz...I'm gonna take a stand and represent my side for fenders. Not that I'm trying to persuade you, (Really I'm not)
I represent Whizzers....did I tell you my Headquarters is in Texas? I was station there in the 70's? Gotta Love Texas!!!

Now... I'll let my fenders do the talking for us
They really do serve a purpose.

Get well Buddy!

Ray