Thurnau

Hello, I just got a new bike and something feels wrong. The pedals feel like they have the slightest wobble to them while pedaling, as if the crank or pedal is bent slightly. What is wrong? It isn't terrible, but slightly uncomfortable.
There is a long story behind my new bike, but it is a 2009 trek 3700 3 series. It has a sr-suntour crank, and plastic wellgo pedals.

Jeff Wills

It could be:

• a cross-threaded pedal
• a bent crank
• a bent pedal spindle
• a bad pedal bearing
• a bad crank bearing

None of these are acceptable on a new bike. Take it back to the place you bought it from and tell them to fix it.

Thurnau

Thanks for the reply, I was hoping it was something more simple. I am going to take it back for a look at. I should have bought a bike rack while I was still there!

freako

It's possible the mechanic that put the bike together misthreaded-or crossthreaded the pedals and thus the wobble-but both pedals? It could also be a problem with the the pedals themselves since these are very inexpensive $20 pedals and Wellgo has had many issues with these and their other pedals-but you get what you pay for.

I assume you got these because you like the platform design then I think if you up grade to Shimano PD-M324 Pedals, these would offer high reliablity and offer two choices of either a platform pedal on one side or SPD clipless on the other in case you later decide to go with clipless shoes thus you would not have to buy another set of pedals and thereby saving you money both ways over the long haul. By the way the Shimano are about $75 on line, BUT again think of the reliability and no need to buy another pedal if you ever go clipless.

But if your never going to go with a SPD system then try the DK Iron Cross that start at about $30.

Either way you need to take it back for a warranty adjustment.

operator

Or the whole crankarm is loose. Which is more likely on a new bike.

Thurnau

Can I go to any Trek Dealer? Or the one I bought the bike from?

Thurnau

Well the kickstand is a little loose too, but I didn't join this forum for troubleshooting that

I will look at the crank arm and see if something is wrong.

Thurnau

The pedals do not look cross threaded because they are in all the way. The crank arm doesn't feel loose, but I see a small gap about 1/16" between the crank and the crank arm. I do not have an allen wrench big enough to test it though.

BayAreaBoy

Regardless of what the actual problem is, it's a brand spankin' new bike that you bought from what I'm assuming is a reputable dealer. Take it back to that particular shop and tell them the bike doesn't work the way you want it to and they should fix it. The shop should have had some kind of fit or service plan associated with the bike anyway. Any reputable shop will be willing to work with you and figure out what the problem is.

Thurnau

Also it doesn't wobble like it is loose and rattles, it feels more like it isn't symmetrical or even.

Thurnau

I took it to the trek bike store today to fix 4 things. For the pedals, they said something was wrong with them. They were missing the little cap that prevents dirt from getting inside. I was gently accused of removing them 4 times, and that they fixed it under the warranty.(i picked up this bike yesterday and removed nothing) The pedal still feels awkward, and after another short ride I limited it to the left side only, which makes me think that the left pedal axle is bent slightly. The were polite, but I just don't think they understood. It isn't worth the aggravation and bike disassembling to bring it back again. Any good cheap plastic bike pedal recommendations to buy online?

Mondoman

Before you go buying parts, might I suggest taking the bike to a different bike shop for a quick, few-minute evaluation by a mechanic, even if you have to pay $15-20 for it?

cooker

Is it possible the pedal was crooked on your last bike so it feels weird on this one in contrast?

Retro Grouch 

I'm going to side with operator.

On brand new bikes a slightly loose left crankarm is way more common than it should be. The torque spec for that bolt is generally around 30 lb/ft. That's more than you are likely to achieve using a multi-tool or 6" long allen wrench. If that's the case, and you ride the bike without getting it fixed, you will hose your crank arm and it will have to be replaced.

Thurnau

My last bike was a 19.5" 3700 trek 2008. I had it for 1.5 months before I realized I needed a bigger bike. They let me trade it in for a 21" 3700 trek 2009 and I paid the difference. I told them what was wrong and I came back an hour later to pick it up. I still noticed the problem, but it is only a slight weirdness.

They fixed the loose kickstand, put air in the tire, looked at the front brakes which were fine depending on how you put the front tire on, and put little caps that cover the hole in the petal. Maybe they didn't even ride it, I am 6'3"on a 21" frame, and the mechanics all looked well under 6'.

Thurnau

I tried to tighten it with a 5/16 allen wrench socket bit on a 3/8" socket wrench. It was so tight I could barely loosen it to try to re-tighten it again. It is all the way in so I do not think it is cross threaded either.

Thurnau

Operator and Retro Grouch you might be right. I loosened and then re-tightened the left arm and it didn't go away, but did feel a lot better. What do you recommend I tighten it down with some more?

misterE0

i had a left crank arm problem on an 07 Trek 3700. I had endless left crank arm issues. No matter how much it was torqued, it'd still come loose. I had it in the shop about 4 times for the same issue. I think they replaced the bottom bracket in the end and that seemed to fix it.

griftereck

loose feeling pedals

who'd have thought it

lots of pedals feel wobbly

Thurnau

I think it was the left arm. I used a 3/8" socket wrench driver, with a 5/16" allen bit, and a cheetah pipe. I over-torqued it slightly, and almost stripped the bolt/screw. I had to beat on the socket to pull it out.

demoncyclist

Stop using the 5/16 allen wrench!!! All common bicycle fasteners are METRIC. If you try to reach the proper 30 ft. lb. torque spec with the wrong sized tool you will round out something. If you are lucky it will just be the tool, not the crank bolt. If you insist on doing this yourself, get the right damned tool- a TORQUE WRENCH with the proper bit for the job.