Viewing 23 posts - 1 through 23 (of 23 total)
  • Largest cog on a 9 speed casette
  • cyclepathologist
    Free Member

    I’ve bought my friend a Ramin 1 with the single chainring and 9 speed cassette. The 34t cog is proving to be too tough for her on the steeper ascents where we live so I’d like to fit a casette with an easier gear. She’ll never be hooning it around so the small tooth cogs are not really an issue. They can be as big as they come but the easiest / largest cog needs to be big! I’m thinking that a 36 tooth cog isn’t really going to make that much difference over the 34t fitted.
    How would I go about fitting easier gears for her? Either 9 speed or even upgrade to 10 speed with a new mech, chain and shifter if needs be.

    simondbarnes
    Full Member

    Can you not fit a smaller chainring?

    ampthill
    Full Member

    I think 36 is it for a 9 speed

    I’d say the solution is more chain rings. Which depending on chain wear won’t cost that much

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    Bazz
    Full Member

    Sounds like a smaller chain ring would be the best solution, what’s on there at the moment?

    davewalsh
    Free Member

    +1 for smaller chainring. What’s on it at the moment?

    cyclepathologist
    Free Member

    This probably wouldn’t work but what about removing the smallest cog from the current cassette and putting 40t cog on the other end if you know what I mean?
    Edit. Like this? http://faqload.com/faqs/bicycle-components/drivetrain/wide-ratio-9-speed-cassette
    Edit. Edit. It’s a 36 chainring currently
    Edit.Edit.Edit. The bike is brand new. She loves it or at least she say’s she does and won’t hear of changing it on the Evans “Right bike guarantee” exchange scheme.

    transporter13
    Free Member

    Largest for 9spd is 36t…used on the shimano alivio 12-36 cassette from crc @£9.99 iirc

    davewalsh
    Free Member

    Well it looks like that would work but you’re looking at about fifty quid for the big sprocket and that’s before you start buying cassettes to butcher.
    Whereas a 30 or 32t chainring would achieve the same effect for £26 from superstar.

    cyclepathologist
    Free Member

    This is great stuff! Thank you. I’m learning as I go with the mechanical side of things so please bare with me. If I order one of these http://www.superstarcomponents.com/en/i-o-chainring-narrow-wide-style.htm and the chainring bolt tool, is it as easy as unbolting the chainring and bolting the smaller replacement back on or does the crank arms / bottom bracket arrangement need to come out? Isn’t bolt dead centre or something like that a consideration and if so, how can I found out if the current chainring matches the replacement from Superstar?

    docrobster
    Free Member

    Is it a 32 chainring as standard?
    32×34 is not that low on s 29er for a beginner is it?!
    30t chainring and 36 cassette is not s lot lower gear really.
    Does the crank have tabs for a granny?

    Junkyard
    Free Member

    I added a 40 Tooth to a 9 speed and it works fine

    As noted other methods are cheaper but also reduce the top end range where as this just increases the low end range.

    Is the superstar extender not the same price as the thick thin ?
    Not sure as I dont buy them as the owner is a ****

    cyclepathologist
    Free Member

    Top end range isn’t really a worry Junkyard. She’s only ever going to be going for a gentle bike ride rather than full on mountain biking or fast riding. Is it as easy as taking the smallest cog off the front of the existing cassette and putting the new 40t cog on the back? I’m wondering if it will need a new, longer rear mech?
    She loves the bike, just not the hard gearing.

    Junkyard
    Free Member

    It depends
    Mine worked with a standard long cage 9 speed XT but did not work with my standard X0 rear mech – long cage

    Yes the process was take off one cog and replace

    IT DOES NOT WORK WITH EVERY CASSETTE AS YOU NEED
    It did not work with my 32 tooth XTR as the gap between extender and 32 tooth was non existent
    It did work with a 34 tooth – SRAM something or other but i cannot say for certain that it works with all combinations as my experience is it does not. but can be made to work with the correct combinations

    cyclepathologist
    Free Member

    Ahhh….it might prove to be the trickier option then. Thank you. So, can I unbolt the current chainring and pit the smaller on without taking the cranks out of the bb? I’d need to buy crank removal tools, bb tools, YouTube crank removal, swear lots, skin knuckles…. Unbolting the current and reboot the new would be ideal. How do I check the new chainring is the same bolt distance? I’m a learner mechanic but I’m keen.

    Junkyard
    Free Member

    all chain rings have a BCD measurement you need to know this and buy the equivalent

    You should not need to remove the cranks to do this

    Where do you live as someobe can lend you tools from here no doubt

    cyclepathologist
    Free Member

    I really appreciate the help. It’s great.
    How do I measure the bcd of the existing ring?
    If I’ m reading this right, I match the new chainring bcd with the existing bcd, unbolt the the current chainring without having to remove the crank from the bb and bolt the new chainring on?

    ampthill
    Full Member

    This bike is advertised as having a 32 tooth chain ring. If i has more than that I’d ask Evans to take a look

    I’d take a look at a 36 tooth at the back as well

    http://www.evanscycles.com/products/pinnacle/ramin-one-2015-mountain-bike-ec071312?promo_cmp=homepage_small_banner_4&promo_ad=Homepage*UNITED%20KINGDOM

    Did you look at the Lithium. The down side is a that its 2 inch tyres max. But similar money for a better range of gears

    http://www.evanscycles.com/products/pinnacle/lithium-two-2015-hybrid-bike-ec071280

    davewalsh
    Free Member

    To find out the BCD you need to measure the distance between the centres of a pair of opposite chainring bolts. Most MTB’s are 104BCD (hence that’s why most replacement chainrings are the same) but there are some oddball sizes out there. Failing that I’m sure if you post the make and model of crank then someone on here will know what the BCD is.
    You can swap the chainring for a 32t without removing the cranks, not sure of you will get away with it with a 30t as the clearance on the inside of the ring will be slightly smaller.
    Also, you may need to take a link or two out of the chain depending on what length it is, the only way to be certain of this is to put it in the smallest sprocket once the new ring is on and make sure the chain doesn’t go slack.

    Junkyard
    Free Member

    yes and if it is 32 it will almost certainly be 110 BCD as 38 is the smallest for 130 BCD

    davewalsh
    Free Member

    Just noticed you’ve posted the model of bike above. Looking at the spec, the chainrings will be 104BCD, however if it’s already got a 32t chainring then the best option would be to fit a double chainset IMO.
    Obviously this is a more complex job as it would mean either removing the chainset and fitting a granny ring if the crank has the tabs for one, and you also may need to change the 32t ring for a ramped & pinned one, or fit a new chainset.
    You’d also need to add a front mech & shifter as well.

    cyclepathologist
    Free Member

    Thanks again for the advice. I’ve checked. It is a 32t chainring. I think I might suggest a 36t cassette and see how it goes. She particularly liked the Ramin 1 because of it’s mountain bike looks, single chainring and option to keep the fat tyres or go for slimmer tyres for less off road kind of rides.
    If that still doesn’t suit, I’ll get a 30t ring in 104 bcd.
    Thanks again for all the help.

    cyclepathologist
    Free Member

    I purchased a 30t I/O chainring from Superstar but the chainring bolts, both male/female, threaded/non threaded are too wide for the threaded holes on the new Superstar chainring. I’m aware that single, double, triple chainring bolts differ in length but I assumed they would all be the same diameter. It appears not to be the case. Does anybody know which chainring bolts I need to buy?
    Thank you

    kayla1
    Free Member

    Shimano and SRAM/Truvativ use different diameter threads on their chainring bolts so you might need to buy some new ‘generic’ bolts as well. Gotta love the standardisation in MTBs, eh? 😆

Viewing 23 posts - 1 through 23 (of 23 total)

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