English Forum Switzerland

English Forum Switzerland (https://www.englishforum.ch/forum.php)
-   Transportation/driving (https://www.englishforum.ch/transportation-driving/)
-   -   Need help with bike, I offer help with cars and computers! (https://www.englishforum.ch/transportation-driving/26215-need-help-bike-i-offer-help-cars-computers.html)

emilian 14.06.2008 22:56

Need help with bike, I offer help with cars and computers!
 
Ok, might sound a bit strange, but:

I have just bought a used mountain bike (my first real bike) and I have some mechanical issues with it (dragging hydraulic brakes i believe, and some noise in the hub of the rear wheel). I can't figure it out by myself, and the bike repair shops charge a fortune, and have waiting lists of several weeks.
I really need help with fixing it, I hope one of you guys could give me a helping hand.

I do car electronic stuff for VW/Audi/Skoda/Seat. Diagnose, and chip-tunning. Also, with any IT related issues - always happy to help.

ManBearPig 14.06.2008 23:13

Re: Need help with bike, I offer help with cars and computers!
 
Regarding the noise from the rear hub, the bearings may have to be overhauled.

Here are couple of good resources:

http://sheldonbrown.com/cone-adjustment.html

http://parktool.com/repair/readhowto.asp?id=105

Good luck!

Eire 15.06.2008 10:41

Re: Need help with bike, I offer help with cars and computers!
 
What type of brakes do you have?

emilian 15.06.2008 10:57

Re: Need help with bike, I offer help with cars and computers!
 
Thanks!

I would need hands-on help though, the tasks at hand exceed my mechanical skills.

emilian 15.06.2008 11:38

Re: Need help with bike, I offer help with cars and computers!
 
Hydraulic brakes on rotors, two pistons per caliper.
The bike is a Merida Matts with most of the components Shimano.

Woodsie 15.06.2008 15:53

Re: Need help with bike, I offer help with cars and computers!
 
We will need more information. There are over 25 different models of the Matts, and they come with different brands and models of brake. We can only help if we know the brand of brake and happen to be familiar with it.

One thing to try is to remove the wheel. Then with a large, flat bladed screwdriver push the pads apart. Then put the wheel back in and pump the brake lever until the pads are in place again. This should set the brakes at the right gap.

If it still rubs then have a look and see if it is only rubbing on one side. This will mean that the brakes are off centre. The most common way of fixing this is with most calipers if you loosen the mounting bolts you will notice that the holes they go through are elongated allowing the caliper to be moved from side to side. With these bolts loose, squeeze the lever then retighten the bolts. This should centre the caliper and stop the rubbing. Other brakes have small, spacer washers and you have to add or remove washers to centre the brake properly.

I would offer to help in person, but my mum is in town and I am busy this week. If you are still having problems by the weekend I may have some time on the weekend, but won't know until nearer the time.

PS. Can you make my 1998 BMW 540 go even faster? :msnwink:

FriendlyKiwi 15.06.2008 22:37

Re: Need help with bike, I offer help with cars and computers!
 
Quote:

Originally Posted by Woodsie (Post 248145)
Can you make my 1998 BMW 540 go even faster? :msnwink:

I cannot, but I can translate your cars internal bus communications to plain english and you can site back and be amazed at the amount of data communications your 540i has.

And reprogram a few things ....

emilian 15.06.2008 23:27

Re: Need help with bike, I offer help with cars and computers!
 
I'll take some pics of the bike and post them tomorrow.

For now I have brought with me only the tools for VAG (VW/Audi/Skoda/Seat). I can do something with pretty much every german car, better results are seen on the turbocharged ones.

stebot 16.06.2008 00:50

Re: Need help with bike, I offer help with cars and computers!
 
though pictures may help , the posters who would like to help you are just asking you to tell them some info so they have an idea if the problem involves a simple cone adjustment , or if they are gonna hunting down a hard to find hub , rotor or pads

are just the rear brakes rubbing , or both front and rear ?
Shimano brakes ? Shimano hubs ?
24 , 27 , speed ?
are your wheels true ?
what kind of noise from the hub ? loud , squeaky , grinding , constant intermittent ?


some bike nut's may not have cars that they need to communicate with
so maybe you should help them help you

Woodsie 16.06.2008 01:05

Re: Need help with bike, I offer help with cars and computers!
 
What is the world coming to when modern car nuts can reprogram a VW Golf to think it is an F1 race car, but are a bit nervous when it comes to using a spanner? :msnwink:

emilian 18.06.2008 15:22

Re: Need help with bike, I offer help with cars and computers!
 
Yes indeed!
If it was a cheapo bike i would not have second thoughts about fidling around with the spanners unfortunatly not the case...

I've been away last couple of days on a business trip.
I'll take photos of the damned thing tonight and post them here.

Thanks!

emilian 18.06.2008 21:39

Re: Need help with bike, I offer help with cars and computers!
 
4 Attachment(s)
Here are some pics, i was wrong ... shimano are some other parts.

Woodsie 18.06.2008 22:39

Re: Need help with bike, I offer help with cars and computers!
 
Oh noes! Hayes HFX-9 brakes. I hate those brakes. :msnmad:

But they do have the elongated mounting holes on them, so the instructions I gave before should sort them out. If not, then they probably need bleeding. Sorry, but I can't help you with that. Some people I know have the knack for bleeding Hayes brakes. I will probably get so frustrated as to throw you bike through a brick wall. :msncrazy:

Anyway, have a go at centering the caliper as described below and check that the disks are not warped and let us know how you go.

emilian 19.06.2008 00:54

Re: Need help with bike, I offer help with cars and computers!
 
Ok, full story:

I had a flat tyre on the rear, took the wheel off and replaced the tube. I might have been a bit overzealous when washing the rear wheel with a water jet, because after I've put the wheel back a noise like having sand or something trapped inside, appeared.
The wheels i believe are true, seem to spin right.

The brakes have a intermitent sound, as if the rotor would touch the pads at some stage in the rotation (not completely sure if that is the cause though.) and it is more pronounced on the front wheel.

Woodsie 19.06.2008 10:47

Re: Need help with bike, I offer help with cars and computers!
 
Take the wheels out. Use a flat bladed screwdriver to push the pads apart. Do this carefully and gently. Put the wheels back on and give them a spin. If it still makes the noise it is a problem with the hubs and you will need to take it into a bike shop.

Otherwise do the things I outlined earlier and that should sort it out.

If it is intermittent, then there is probably a small warp in the disk (not the wheel). You can gently bend the disk back fairly close to straight with your fingers (DO NOT USE TOOLS FOR THIS, YOU WILL DAMAGE THE DISK, EXPENSIVE).

Also, remember, disk brakes will nearly always rub a little. This is normal and has no effect on the performance of the brake. With practice you can almost completely eliminate it, but this takes time, experience and patience and a light rubbing sound will often return within a couple of rides.

emilian 21.06.2008 17:51

Re: Need help with bike, I offer help with cars and computers!
 
It looks like the front disc is rubbing against a part of the caliper, not the pads. Strange enough, the rotor seems pretty straight.
The rear brakes need only slight adjustment.
The noise in the hub ..cannot figure out the source of it for the life of me.


I don't have the right tools to do the adjustments .. can someone help me with that? I am not looking at buying them, since i leave in one month and probably sell the bike ...

Eire 21.06.2008 18:13

Re: Need help with bike, I offer help with cars and computers!
 
Use a 5mm alan key and loosen the caliper retaining bolts. Once the caliper is loose see if you can move it in such a way that the disc would not catch on the calliper any more. IF you can get a business card or an old SBB ticket and stick it in between the disc and the pads on the side its catching. Pump the brake lever a few times, and then pull it tight. Hold it tight while tightening the retaining bolts.

If this doesn't work then you either need new brake pads or if the calliper can't be moved by hand far enough to stop the disc from rubbing on the calliper then you may need some shims to put inside the disc to space it out from the hub.

emilian 22.06.2008 22:45

Re: Need help with bike, I offer help with cars and computers!
 
I took the pads out and pushed the pistons back, while pushing some of the fluid got out. When pumping up the lever, nothing happens - so I presume I now to bleed the brakes. I have some Castrol DOT 4 brake fluid which i used for my car, would this be good?

And once again, if one of you that is experienced with kind of things could help me, would be really nice. (of course I'll pay, and beers on top :-) )

Woodsie 23.06.2008 10:48

Re: Need help with bike, I offer help with cars and computers!
 
This is why I hate Hayes brakes. The simplest tasks always end up far more complicated than necessary.

If the fluid came out of a small hole in the front of the caliper it sounds like a bleed should do the trick. If the fluid came out of anywhere else then the brakes need repairing which requires professional help.

Unfortunately I do not have the tools to bleed Hayes brakes. You will need a Hayes bleed kit http://www.chainreactioncycles.com/M...x?ModelID=8384. You can use the little bottle in the kit, but it is better to replace it with a 50mm srynge. The critical part of this kit is the little black plastic nipple. Without that you cannot bleed a Hayes brake. This kit comes with brake fluid. You can also use any other Dot 4 brake fluid. Make sure that it is not more than a couple of months old and has been kept in a sealed container else it absorbs moisture and is useless. Dot 5.1 fluid is better.

Unfortunately my time is still very tight at the moment. You couldn't have chosen a worse time to ask for help from me. But get the bleed kit and give it a go. The process is pretty straightforward, but requires patience and persistence. Tips I remember:

- Tap the brake lines with a screwdriver to dislodge any air bubbles which my be trapped.
- Do not loosen the bleed valve too much else air can leak in there.

I learnt how to do this the same way as all my mates. Sitting in a shed and trying it, getting it wrong a few times, getting the hang of it, then getting the ****s after a year of this and buying a different brand of brakes.

emilian 30.06.2008 23:43

Re: Need help with bike, I offer help with cars and computers!
 
Ok, I have tried just about everything! The only result is the floor of my cellar soaked with brake fluid ... it's not as easy as reading a pdf about it, if you never seen someone actually do it. Can anyone in here actually help me with this?


All times are GMT +2. The time now is 13:22.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
LinkBacks Enabled by vBSEO 3.1.0