Questions & Answers

49 thoughts on “Questions & Answers”

1. Hi Relja
   Can I use Campagnolo Centaur 10 speed, chain and derailleur, on an Elite Zumo smart trainer with a Shimano 10 speed cassette?
   Many Thanks in advance.
   Kenny

   • Campagnolo 10 speed cassettes have different pitch, while their 10 speed chains have different width, compared to Shimano 10 speed ones.
     So I would not expect it to work very well, but haven’t tried it. Sometimes, close enough works satisfactory, sometimes not. In this case – I would expect shifting to be rather poor.

2. Thank you very much for your speedy reply 🙂

3. I am looking for a Suspension seat post for a Raleigh witch is 36.1 But none of the post match that size

   • While I like to think I’m a wizard – making 20+ year old bicycles and computers up and running – suspension stuff is out of my area of expertise. 🙂

     Hopefully, an expert on the topic will come across these comments and provide a shopping link.

     An alternative could be using a shim to fit a smaller diameter seatpost – if such can be sourced (both the seatpost, and a matching shim).
     Shim can also be machined. With a DIY option of cutting a can of beer, or some poisonous sugar filled “soft drink” (yack! 🙂 ), making shims out of that, to match the difference in diameters. Minding it doesn’t slip inside the seat tube (hard to take out later) – leave some “lips” protruding out and aside, to keep it in place. And minding not to cut oneself when making and fitting it.

4. Thank you for that I will look in to that

5. Hello. I have a few Sram max shift 3.0, 7 x 3 grip shifters that are new im trying to use up in my shop. I have in-fact through the years used these with some types of shimano rear derailleurs, but do not remember which shimano, i think tourney, mabye alivio. My question is for an atb which Derailleur from shimano, least expensive can i use for the rear with my last few new pairs of sram grip shift shifters? Sorry for any confusion. I have always been a shiman person, i just want to know how i can use sram with shimano without breaking the bank on a sram derailleur. Thanks much

   • I’m not sure which standard that shifter is. As I’ve noted in the rear shifter compatibility article, 7 speed SRAM shifters were made in a Shimano compatible cable pull configuration, as well as using SRAM’s “1:1” cable pull.

     If the shifter is 1:1, it will only work with SRAM 1:1 rear derailleurs (and, based on my calculation, but I haven’t tested this – with Shimano 11 speed road bicycle rear derailleurs, and Tiagra 4700 10 speed road RD).
     If the shifter is a “Shimano compatible”, then it should work with Shimano rear derailleurs for 6 to 9 speed, as well as with non-Tiagra 4700 10 speed road RD-s (but not with 10+ speed MTB RD-s).

6. Can you help? Thanks.

   I have a new Tiagra triple front rapid fire shifter and an existing Shimao ALTUS front changer mech e-fitting (ie via bottom bracket). I have wired everything up and I cannot change over three chain rings. To change over two rings works but not three. I have adjusted the limit screws and the tightness of the cable. I cannot get it to work. What am I doing wrong? I have seen that rapid fire shifters are normally compatible with most front changers. Thanks very much, Andrew

   • Tiagra 4700 (newest, 10-speed) shifters pull a lot more cable than the other, pre Tiagra, and most MTB front shifters.
     So Tiagra shifter could be pulling a lot more cable per shift, than the front derailleur (Altus) needs. That could be causing the problem.
     While first click can be configured to properly move the FD to the mid. chainring, the 2nd click probably wants to pull the FD too far out – so FD stop prevents the movement, and shifter can’t reach it’s click point, to stay in gear.

     If it is adjusted so that the 2nd click (pulling cable) puts the FD right over the largest chainring, then I would expect the first shift-down to move the FD too much, so it doesn’t stop at the middle chainring.

     I would get a Tiagra FD to solve the problem. Or choose some other front shifter.

     See the article on front shifter compatibility (including the last chapter “Trim option”).

7. i usually use either velox or zefal rim cloth adhesive rim tapes as these have never failed on me,the secret to using these rim tapes is get ones that go past the rim holes well,if you use the skinny 13mm ones they will slip past the rim holes,17mm ones are good for most road bikes.at the moment there seems to be a worldwide shortage of these rim tapes and just wondering if any readers have a home made solution.

8. Please could you help? I have a road bike with shimano 7 speed cassette and twin chainset, indexed gears.
   I am struggling to find bits to renew the drive chain . . . . I have located a chain , and a cassette. I am struggling to find 130 bcd chainrings withbthe correct number of teeth. Well I have found some, but they say they are for 10/11 speed. Are rhese going to be ok with my set up. If not what issues would i experience?
   Thank you

   • Hi Chris,

     Are you replacing only the chainrings – while keeping the cranks?

     In that case, I’d just make sure that the new chainrings can be bolted securely and give it a test ride. Expecting it to work OK.

     Relja

9. you can buy new 8 speed chainrings that are 130 bcd ,7 speed and 8 speed chainrings are the same,130 bcd and 135 bcd are very common sizes.most teeth sizes are available,10 or 11 speed should still work but those chainrings will be thinner.

10. you could even replace the whole crankset complete with chainrings,sometimes that actually works out cheaper

    • there are alot of retro style remakes being made in double chainrings complete with cranks,the 7 speed alloy cranksets can usually be found on ebay,some bike shops have them too.type in retro parts when chasing up spares for older retro style bikes,google will find all parts on the market,if it does not show up in google then most likely the part is no longer on the market.

11. Hey guys new to riding again. Just bought a small ebike offline from China. Its has seatpost clamp measures 34.9 but there are no measurements on actual seatpost. Original shipped to me bent and now its too hard to adjust seat height when riding and putting in my car and needs to be replaced.
    I have no idea what size post I need to buy and which one is strong and tall enough to fit my frame of 6’4 and 370lbs.
    I was looking at Thompson Elite, Thudbuster Lt, Ritchey, and Syntace. But I don’t know which to go with to hold my weight and is tall enough for comfortable ride.

    Also, need to extend factory handlebars because they are too short as well. Need new stock bars for low-end HD Tea electric bike I found on ebay.

    Thanks for any help and advice you can offer a newbie
    Char

    • Hi Char,

      As I like to say: “One good measurement is worth a thousand expert opinions.” For more details, see:
      Seatpost diameter standards and how to measure them

      After you are certain which size (diameter) you need, measure which length you need. For that you should consider:
      Minimum seatpost insertion length
      I.e. add that to the amount of the seatpost sticking out of the frame.

      Once you have those important measurements, you can start looking for a matching seatpost that is strong enough.

      Ritchey generally makes decent quality stuff – but avoid their “WCS” (World Championship Series) components since they are built to be as light as possible, at the expense of any “needless” extra weight (and strength).

      Generic, cheap, Chinese-made steel seatposts can be heavy but very strong (though not always, unfortunately).

      What I often do is go to a local bicycle shop I trust and plainly ask “what’s the cheapest that’s any good.” They usually know which models are least often returned.

      That’s especially effective nowadays when most manufacturers change models each year, making them sometimes better, sometimes worse. Bike shops that sell a lot of parts get feedback relatively quickly.

      Hope this helps. 🙂

      Relja

12. hi,
    I have a doubt regarding the shape of bicycle forks. In general they have hollow tube shape. why cant they be made into I sections so that they can have a high bending strength when compared to hollow tube shapes. and also why hollow tubes are mostly preferred over other shapes
    Don’t mind if it sounds silly. Thank you

    • Hi Rock,

      Hope this helps – for a start:
      Bicycle frame design explained

      Relja

13. the way they make steel bicycle forks now is the best design ever,proven design over many years,if you made them in sections that would be expensive and also would be heavier and possibly weaker at the joins,the way old chromemoly bikes were made is the safest,strongest most durable frame ever made,you will hardly ever find an old frame that got bent or cracked,unless it got a serious beating,forks only bend or break if bike is not used properly

14. weight is also an issue on any bike which is why bicycle tubing is hollow and that rounded tubing also adds to the bicycle strength,you cant find a better material than traditional steel bicycle tubing,its ultra tough.i doubt if they will ever find a better material than cromemoly to build bicycles from,steel bicycles still running from the 1970s and 80s says it all,bicycle tubing is lightweight,tough and very very durable and quiet easy to work with compared with other modern materials.you can silver solder it,weld it or braze it.

15. take a look at some old gaint mountain bikes from the 1990s those bikes were over engineered and you could not bend any part of those bike if you tried,even those forks you could not break them,oversized steel tubing they had and the early ones had no suspension at all but those bikes rode on the roughest of trails and nothing bent or cracked,the early bmx bikes were just as tough.

16. Hi Relja
    Thank you for your recommending and infirmation.
    I have plan to change my 3*9 system to 2*11 speed and my front derailleur is fd m530 that shimano said min different between top and intermediate 12T and front chain wheel tooth differwnce is 22T.so my new system of crankset is 26*36 and rear sprocket is 11*42. Can i set my m530 front derailleur to my new system or i have to purchase a new 2 speed front derailleur m7025 h?

    • Hi Amir,

      I’d give it a try. Triple front derailleurs can handle a 10-tooth difference with no problems.

17. Can i fit a 12t cog to a thread type flywheel?

    • Hi Jonathan,

      I’ve seen freewheels with a smallest sprocket of 12 teeth. So I suppose it is technically possible.
      I’ve never seen one starting with 11 teeth though.

      However, a vast majority of modern freewheels start with 14 teeth on the smallest sprocket.
      Models with smaller sprockets come from manufacturers that aren’t Shimano – like SunRace, Miche, etc.

      Having said that, I can’t find models with fewer than 13 teeth today. Even that is exotic. 14 teeth seems to be the norm.
      The same goes for the single-speed sprockets – if that’s what you are asking about.

      If top speed is a problem, a solution could be sourcing front chainrings with more teeth (48, 50 or 53).

18. Can I use my Claris 8 speed crankset with Sora 9 speed Rear Mech and cassette?

    • Hi Abhishek,

      Yes, Claris cranks won’t mind having a 9-speed chain.

    • Also, will it be better if I use Sora FD or Claris FD?

    • Sora is a bit higher end FD. But it should work fine with Claris as well. All else being equal.

19. Hello!
    I was just wondering, I have an Sram X9 rear derailleur which has exact actuation and I’m searching for a cheapo STI (ltwoo or sensah) to match it but they won’t give me info on their cable pull ratio. Is there any cheapo STI compatible with Sram X9 type 2?

20. my best advice is if you have sram gear,then go with all sram gear,if you have shimano gear,go with all shimano gear,dont mix and match different makers parts or you will come across compatabilty issues.

21. Hello Relja!
    I need help !!
    I recently bought a hybrid bike bianchi comaleonte, and I am trying to swap it into some sort of gravel bike. 🙂
    It was equipped with shimano deore RD and alivio FD M430.
    I have bought sora R3000 sti 3×9 shifters. Brakes and rear derailleur works great, but I can’t match FD and left shifter. The cable pull from sora R3030 left sihter is about 13,5mm an the cable pull from alivio shifter is about 20,5mm. Is there anything I can do??
    What about purchasing a FD R3030 triple?? Will it works on treking FSA crankset 48/36/26??
    Thank you in advance!!

    • Hi Mikula,

      I would expect a triple road FD that’s compatible with the shifter (like the FD R3030) to work better.
      Yes, it’s designed for a 50T largest chainring, and has a stated total capacity of only 20T (48-26 is 22), but unless lightning-fast shifting is only acceptable, I’d expect it to work OK.

22. very many thanks 🙂 regards from Slovenija!

23. This website (and all the other BikeGremlin websites) has been removed from the Bing search engine!

    DuckDuckGo, Yahoo, and Amazon’s Alexa all use the same, Bing’s, search engine – so it’s gone from there too.

    I did some Googling and it seems like my website isn’t the only one affected. So, for good search results, it seems like we’re stuck with Google. Google (and Yandex for that matter) work normally.

    Full report of the problem:

    Websites erased from Bing overnight

24. For technical reasons, existing notification subscriptions were all re-set (i.e. deleted, cleared).
    As far as I know, the subscription system should work fine from now on.
    For more information, see the BikeGremlin News & RSS feed page.

25. Hi Relja,

    I am in the process of installing hydraulic brakes on my “2016 Giant ATX 27.5 2” bike.

    My plan is to swap out the “Tektro TKB-172, Mechanical disc, 160mm” brakes which it currently has, with new pre-bled brakes from Amazon (I would hope I can leave the original disc/rotor on?? ).

    Other than the length of the cables of course, is there anything I should take into account before starting ? And could you potentially recommend a affordable pre- bled set of hydraulic brakes ?

    I would be jumping with joy is you replied.

    Sincerly,

    Rodrick

    • Hi Rodrick,

      With hydraulic brakes, the housing is often too long (intended to be cut to size).
      It’s not a complicated procedure, but I’m yet to make a video on how to do it.

      I think there is no need to replace the existing discs. Not unless you wish to start using sintered pads, and your current disc is designated for organic pads only.

      Regarding the brakes, Shimano Altus (BT200 model, the newest one) are surprisingly good for the price, at least in my experience. While Deore (like BT501) are what I’d call very good, without costing an arm and a leg.

      When you buy a new set of shimano caliper+lever, they usually come pre-bled. But, as I said, the hose will most likely be too long.

      A good mechanical brake alternative are Avid BB7 brakes. I love those.

      Hope that helped. 🙂

26. Hi Relja just a question before I buy the part question.Saw the SRAM yaw system on a video and am impressed with how well it works.Just wondering if I have a campy escape ergo front shifter which I believe has no trims just up and down would shift a sram yaw derailleur.Would hate to buy the yaw just to find out that it won’t work.

    • Hi John,

      The Yaw system was designed to remove the need for a trim function.
      Having said that, I haven’t tried it with Campagnolo shifters, so can’t confirm it will work OK. 🙁

27. Thank you very much Ralja just wanted to make the front shifting as crisp as possible without going to a full group set. Really frustrated with the campy 50/34 cranks shifts worse than the 80s friction stuff.Even the campy techs are scratching their heads.What did work was swapping out the rings for a set of matching sram 50/34 rings.That being the case I got an excellent deal on a beautiful SRAM red 22 gxp crankset and thought a matching red front mech might work even better.

28. I have a 2008 [Mongoose XR-75] 21 speed, how do I thighten the crank???

    • Hi Dannie,

      That would depend on the type/model of cranks you have.
      If it’s a square taper and it has become loose, that usually means that the interface was damaged.

      New cranks and bottom bracket axle will most probably be needed. Here is my video tutorial on how to install a square taper bottom bracket and cranks.

29. I want to put thicker tyres on my bike, is this possible, at the moment I have 28 x 1 5/8 x 1 3/8, what would you recommend

    Thank you

    • Hi Jackie,

      The max tyre width depends on your rim width and on how much space your frame offers, and riding conditions and total bike+rider+luggage weight too of course.

      I wrote an article about bicycle tyre sizing and dimension standards. It explains what to look (out) for and what to measure to see if a wider tyre will fit.

      Generally, for off road, you could go as wide as 55-622 mm (if it fits the frame and rims), while for general paved road and dry dirt roads, it usually makes no sense to go wider than 42-622 mm.

      Relja

30. Notification

    Because of some technical problems, it is no longer possible to get email notifications for comment replies.

    For more details, see the BikeGremlin News page.

    Relja Novović

    • The problem has been resolved in the best possible way! 🙂

      From now, for questions or comments, please use the BikeGremlin forum:
      https://www.bikegremlin.net/

      Relja

Comments are closed.