tommyd49

I'm adjusting the derailleurs on my Raleigh Airlite 100 Racer. It's got a two speed crankset on the front and 7 speed freewheel on the back. I've looked at Park Tools, and I've done every thing they've said. It's rides near-perfectly on the bottom 3 gears and the top 4. However, if I use the big ring on the front, and fourth sprocket up on the rear (or anything above), the chain grinds loudly against the outer cage plate on the front derailleur. This is not a light, barely noticeable grind, it is clearly there as it is very loud. I've tried fiddling with the indexing and the L limit screw, but it hasn't helped. Tried searching around for tips as well, but found nothing. Anyone know a way to sort this? Thanks.

Chris_F

You need to move the front deraileur outward. The reason this happens is because the chain rubs against the deraileur when it's in those gears. Try adjusting the front deraileur and you should be able to get it to go away. The problem is that you now may get the same noise in the opposite scenario: small ring and bottom gears. I know on my bike it's nearly impossible to get all gears to work perfectly without this grinding, so I just adjust the gears so that it doesn't grind where I'm more likely to ride. So for the big ring my big rear gears grind and for the smallest ring (I ride a tripple) my smallest rear gears grind. When I get that grinding noise I just switch front rings and find a similar ratio.

HillRider

You need to adjust the "H" (high) limit screw, not the "L" (low). The H screw controls how far the derailleur can move to the outside. If your derailleur can't be moved far enough outside, the chain will rub it in the smaller cogs. Back out the H screw until the chain spills to the outside on the shift, then turn it in 1/4 turn at a time until it just stays put.

tommyd49

Sorry. I said it was grinding against the outer cage plate. It's not: it's grinding against the inner plate.

Peedtm

Something else to check is the alignment of your front derailleur. Ideally, you want it exactly parallel to the chainrings, but sometimes you need a little tail in (in your case) or tail out. Also make sure it's 1-3mm above the big chainring as well.

DMF 

H screw may be too far out. L screw has nothing to do with this problem.

Is the front shifter indexed?

HillRider

The OP first said the chain was rubbing against the outer cage plate so that is the problem I tried to correct. If it's the inside of the cage, the L screw could be turned in much too far or **********?

tommyd49

Yes

well biked

I did a little editing to this statement in your original post, with my edits in bold. Does this accurately describe the problem? If so, and since you say you've already used the Park tool site's instructions for adusting the derailleur, it leads me to believe that your bottom bracket spindle is too long and the problem you're having is caused by an improper chainline.

Is the front shifting responsive (no unusual delays or sluggishness) when both shifting from large ring to small ring and small ring to large ring? The derailleur cage is aligned as the Park tool instructions say? No problems with the chain being thrown off either to the inside or to the outside? If the answer to the first two questions is yes, and the answer to the last question is no, then the derailleur is adjusted correctly, and the problem almost has to be a chainline problem. You might never get it to not rub at all, but it definitely shouldn't rub as much as you describe-

04jtb

I have this problem on my Raleigh Airlite in the two largest in the big ring, and the 3 smallest in the small ring.
I overcame it by not using those gears and just shifting cranks, as 3rd and 4th work on both chainrings

Jack

DMF 

Got a trim position on the shifter?

Flanderflop

Just from experiance...

Fixing stuff in a forum is really tricky... but to summarize:
Check limiter screws,
Check Cable tension.
Check der Hanger Parallel to chainrings and not too high up the seat tube.
assume not trim adjustment in front shifter.

If you have gotting this far, and it sounds like you have, I would take it to your LBS and have a pro look at it before you go switching out bottom brackets and adjusting chainlines.

It is probably worth the $10 to know what you are up against.

tommyd49

Do you know what?

I've been to two bike shops about this. One, the idiot who "fixed it" got it so only half the gears were working! I showed it to him and said it wasn't working. So he started screwing the limit screws all the way in. Then it still didn't work so he said the front derailleur is bent. I didn't really trust his opinion because he was stoned. So I took it to another shop and said it the derailleur was bent and it needed replacing. The next day I collected it and they said it isn't bent so they just adjusted it. It seemed OK in the shop, so I paid then the money, but when I left and rode home, I noticed there wasn't that much improvement in how it had been originally.

I have some great bike shops in my area.

tommyd49

OK, I've decided to just go out and buy a new derailleur. If I and two shops can't fix it, I thought it would be worth spending the £10 to buy a new one and see if it fixes it. The one on before was some piece of crap, the make was Logan or something.

Anyway, the one I bought was a universal Shimano. I'm having difficultly putting it on though. As it's a universal, it's designed to be used with thicker frames than the one I've got. It comes with spacers for mounting on to thinner frames, but it's been an absolute pain to try and fix it on. So has anyone got any tips and how to fit one of these?