Impulse buy, a bit of help needed

[Stantheman]

My son has out grown his bike so I’ve been looking at secondhand adds for a few weeks. Saw a Btwin Rockrider 500 for £250 and took a look. Like brand new and got it for £200. Only issue is the gear shifting is extremely stiff on both the front and back. Where should I start diagnosing the problem? Has SRAM combined gear leaver and brake leaver. Never had to deal with sram gear before and the online vids seem to point to cable damage. Appreciate any help.

 

[bikingdad90]

Release the cable so there is no tension on the front and rear mechs to see if the mechs move freely by hand, if they do try the shifter end and see if they will move freely. It should tell you which end is stiff. If neither is stiff I’d replace inners and outward and set up the indexing again.

if your not confident with bike mechanics take it to a local bike shop.

 

[Stantheman]

Good stuff thank you. Any big differences between sram and shimano I should be aware of?

 

[bikingdad90]

SRAM is double tap so short shift to go down the cassette tube be at a time and long shift to go up the cassette, a very long shift goes two up whereas Shimano uses the brake lever for the up shift but no major differences.

 

[Stantheman]

That rings a bell👍 Regarding the shifting. Report back when I have had a fettle.

 

[Cycleops]

As well as the above I'd suggest flushing out the shifter with WD40 as well but probably a cable issue.

 

[vickster]

SRAM is double tap so short shift to go down the cassette tube be at a time and long shift to go up the cassette, a very long shift goes two up whereas Shimano uses the brake lever for the up shift but no major differences.

Not sure if sram MTB shifters are?
Unless the OP means Triban not rockrider?

 

[Stantheman]

Rockrider MTB. Brake lever and shifter look to be one unit.

 

[vickster]

I’d change all the cables

 

[Stantheman]

Inners and outers?

 

[Reynard]

Are they twist shifters or trigger shifters?

If the former, it's probably easier replacing the shifters if either they or the cable inners are fubared. Usually, the cable inners are bonded to the mechanism so can't be removed separately. Fortunately, twist shifters are pretty cheap to replace.

Could be worth upgrading to trigger shifters, as they're easier for small hands to operate.

 

[Stantheman]

They are trigger shifters.

 

[Ajax Bay]

https://www.cyclotravel.net/500-btwin-rockrider-review/
SRAM/Shimano issue irrelevant (dad90 is talking about drop bar STI/shifters). If the bike looks brand new then it'd surprising if the cables or the flat bar trigger shifters were damaged or faulty.
GT85/WD40 drowning of the shifters required: squirt through every orifice. If that doesn't work (along with a a clean and squirt for the front and rear mechs), cut (with care) the very end of the rear cable and remove and reinstall it (have a new one ready in case of fraying).

 

[Stantheman]

They guy who sold me the bike did say it hasn’t been used for over a year, stored in his shed that looked dry. I will start with WD40 and go from there.

 

[Stantheman]

Liberal use of WD40 has improved the stiffness. Cables all look good and cleaned and lubed them. Released the cable from the rear derailleur and the is no stiffness at the shifter. When the cable is reconnected it’s stiff to shift but much better. Compared to my shimano set up it is still a lot harder. Progress has been made though.