Question For Experienced Bike Mechanics!!!

[Cannondale101]

Greetings,

First Post because my old bike broke.

I have a Circa 1995 Cannondale M500 Mountain bike that needs a replacement rear derailleur because it has a broken internal spring.

The gear set is a 3 X 7 speed Shimano Exage 400LX and it appears that these gear sets are no longer available and the Google search for "replacement gears for Shimano Exage 400LX" did not provide any hits so I need to solicit professional help from experienced bike mechanics that would be familiar with the Exage 400LX.

So the questions are:

Should I just buy a replacement rear derailleur unit and if so what unit would you recommend (I want something cheap and a direct bolt on replacement)?

I am not opposed to buying a complete new set including the two handlebar shifters/ two cables/ front derailleur/ rear derailleur but I do not want to get involved in having to replace the gears...I just want something that will be cheap and a direct bolt on. I have automotive experience but know nothing about bicycles

Any help would be greatly appreciated!!!

THANKS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Sharky]

Go to a website like SJS Cycles and ask them. I'm sure that as long as you stick to the Shimano brand, you will be OK.
However to replace the rear mech, you will have to split the chain, so you might as well fit a new chain as well and unfortunately new chains don't always mesh with the old cassette, so would be prudent to replace the cassette at the same time.

These jobs are quite simple, but you will need a few specialist tools - chain splitter, chain whip and cassette removal tool. All worth having in your tool box, but for a one-off job, might work out cheaper if you just popped it into a good LBS. Google searches for most jobs can be found on the web.

Good luck - well worth the DIY strategy in the long term

 

[winjim]

You don't need to split the chain, you can disassemble the mech cage instead. In fact, that's the advised method if you're not replacing the chain. It's about the same level of faff as splitting the chain. However, as it's an older system, it may well be that the chain and cassette could do with replacing anyway, which you might as well do while you're at it.


Edit: I say the same level of faff, for the inexperienced it does seem more daunting as you're pulling apart a fairly major component, but they are designed to come apart, you just need to make sure everything goes back in the right place. Split the chain if you're more comfortable doing it that way.

 

[Pale Rider]

The OP also wants to know which derailleur he needs to buy because his groupset name/number is no longer available.

Seven speed now seems to called Tourney.

I'm aware replacing derailleurs is not always as simple as it appears.

Am I right in thinking this one should fit?

https://www.ebay.co.uk/p/17014646437?iid=402158791787

 

[derrick]

You don't need to split the chain, you can disassemble the mech cage instead. In fact, that's the advised method if you're not replacing the chain. It's about the same level of faff as splitting the chain. However, as it's an older system, it may well be that the chain and cassette could do with replacing anyway, which you might as well do while you're at it.


Edit: I say the same level of faff, for the inexperienced it does seem more daunting as you're pulling apart a fairly major component, but they are designed to come apart, you just need to make sure everything goes back in the right place. Split the chain if you're more comfortable doing it that way.

You might not need to split the chain. But i am not sure your advice to pull the rear mech apart is good. Not for someone who does not seem to have much idea.

 

[Ajax Bay]

I have a Shimano Exage 300LX (RD-M300) which I just fished from my box which the OP can have (it will fit and be compatible). I'll PM the OP. Don't think suggesting splitting the chain is sensible given apparent expertise. Fitting this will need an 8mm spanner and a 5mm allen key, and that's it. The current cage can be taken off (two 8mm screws), chain removed, old RD removed and replacement RD attached (5mm allen key), chain few through (take a picture of the old route for reference and get the chain the right side of the tab), reattach the cage and ride away.

 

[Cannondale101]

Good morning,

Thank you all for your advice...greatly appreciated!!!

Ajax Bay...special thanks for digging out your old RD. My guess is since you are using terms like "spanner" that you are a cousin from the other side of the pond and therefore the cost of shipping might be counter productive. In normal times I find myself in London on a regular basis so I would offer to take you out for a pint the next time I am in town however with the Corona Virus it seems that our Corona beer pub play date will have to wait. "Stay Calm and Carry On"

I found this Tourney unit on our local eBay...will it work:

https://www.ebay.com/itm/Shimano-To...Lv5PairwiseWeb&_trksid=p2386202.c100677.m4598

 

[Cannondale101]

Here is another option...might be a good idea to replace the whole gear/chain set because all of the parts are 25 yesrs old.

Would this work on my Cannondale:

https://www.ebay.com/i/202787849788...pMJKSsr-C7gKZQI3Mve_4VyFQrPopudMaAsYeEALw_wcB

 

[Pat "5mph"]

Mod Note:
@Cannondale101 welcome to CC!
You have PM from @Ajax Bay.
As a new member the system gives you access to the PM function only after you make a few posts.
Mods cannot over ride this, another couple of posts you should have this option

 

[Ajax Bay]

That Exage 300LX RD was just hoping to get some miles in once again - it had a neglected youth before being skipped .
It's your choice but I would stick to replacing the item (RD) that's broken rather than buying a complete set of stuff. Keep it simple. The Tourney one the OP linked to would, as far as I can tell, be a compatible replacement (see below). Its cage is 77mm (c-c) which is less than my 300's 87mm (SGS probably the same as your 400) so the new RD will wrap less. This will make a difference if you'd fitted a silly large large sprocket freewheel/cassette. You can measure your 400 to see c-c the cage length. Also what is the sprocket range (eg 12-32) and how many teeth on large and small chainrings?

 

[Cannondale101]

>ts cage is 77mm (c-c) which is less than my 300's 87mm (SGS probably the same as your 400) so the new RD will wrap less. This will make a difference if you'd fitted a silly large large sprocket freewheel/cassette. You can measure your 400 to see c-c the cage length.

The Exage 400 installed on the bike now measures 97 from center to center

>Also what is the sprocket range (eg 12-32) and how many teeth on large and small chainrings?

The smallest of the rear wheel 7 sprockets has 13 teeth and the largest has 30 teeth.

Thanks again for your help!!!

 

[Cannondale101]

It looks like Amazon has this set available for a 21 speed:

View: https://www.amazon.com/dp/B01GZDZXEI/ref=sspa_dk_detail_3?psc=1&pd_rd_i=B01GZDZXEI&pd_rd_w=Qmw2y&pf_rd_p=48d372c1-f7e1-4b8b-9d02-4bd86f5158c5&pd_rd_wg=vGAjA&pf_rd_r=2RG50EA312KH1ZW7ETR1&pd_rd_r=9ae9fdc7-7f78-44c5-9985-eb2469fff037&smid=AF4TD07ZYC9ZQ&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzMkYxQzBTS1RKOEZLJmVuY3J5cHRlZElkPUEwOTc0ODQ0MUs2WFpESjBGOUI0RSZlbmNyeXB0ZWRBZElkPUEwMDIyNTQ4MjNBNjdYWUdXT09RRCZ3aWRnZXROYW1lPXNwX2RldGFpbCZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=


My bike currently has the shifter + brake lever setup so I think this will be a direct replacement

 

[Ajax Bay]

Fitting the FD in that set will depend on your seat tube diameter - Shimano FD-TY500 Front Derailleur 6/7 Speed SIS clamp-on for 31.8/34.9mm OD seat tube.
Think the RD will be a satisfactory replacement:
Technical specifications
Attachment: Direct mount standard
Cage length: long
Max. sprocket teeth: 34 teeth
6 and 7 speeds compatible

 

[Cannondale101]

Ajax Bay...again most grateful for your help!!!

>Fitting the FD in that set will depend on your seat tube diameter - Shimano FD-TY500 Front Derailleur 6/7 Speed SIS clamp-on for 31.8/34.9mm OD seat tube.

I measured my seat tube and it is 32-ish MM so that part is good...and my handlebar diameter is 22-ish MM (what is all of this MM crap...as my dad says... "if God wanted the metric system He would have had 10 disciples" )

>Think the RD will be a satisfactory replacement...Attachment: Direct mount standard

So this part trips me up...Shimano in circa 2012 introduced the "Direct Mount" RD and my bike is a 1992-ish. From what the Google tells me the direct mount simply gets rid of the B-Link and mounts the RD farther back and directly behind the cassette...Huh?!?!?

I have attached a picture of my existing Exage 400LX RD. Can I Ass-U-Me that I can simply use an Allen wrench (do you call it an "Allen Spanner" if it does not span anything) and unbolt the RD from the black hanger bracket and then bolt on the Shimano RD-TY300 Rear Derailleur in its place???

Dang...I need a pint...I think I'm having Wuhan Induced London Pub Withdrawal Syndrome (WILPWS)!!!

THANKS...and Cheers for that!!!

 

[Ajax Bay]

Yes, your current RD (the 400) and the RD in that set are both 'direct mount'. No idea what a 'B' link is. You get three kinds of way that an RD attaches. You want this one and an allen key (5mm I think). For nomenclature confusion see: https://www.cyclechat.net/threads/tyres-on-the-wrong-way-for-over-two-years.219604/ (and definitely not a spanner). Does a 'wrench' 'wren' anything, I wonder? Maybe it does: (Old English wrencan "to twist")
How do you know Jesus didn't actually have 10 disciples and a couple have been added along the way, for reputational reasons?