Latest gym project was an offer on Facebook Marketplace for a scrap exercise bike. Advertised as free, and likely only use as scrap metal. So I went for it as a fun project with the boy.
When I picked it up the previous owner advised it had been well used but eventually the chain broke. He replaced it but never got it to run right and it sat in pieces awaiting inspiration, was eventually replaced with a new one and then offered up for scrap with some bolts lost along the way.
It’s a decent bike, a NordicTrack GX2 Sport Bike. Weighs about 50kg, takes riders up to 120kg and is chain rather than cheaper belt so almost gym quality.
We got it home and with some bolts from the pile of junk in garage we got it assembled. Only missing item was pedals so stuck on some from the spares pile.
Then to find the issue. The boy correctly diagnosed the chain seemed to be sticking on the sprocket and pinging off with every link. A rough comparison with a spare scrap bike chain showed it seemed to be too narrow.
We split the chain and it was a job to pull it off the sprocket. Even with copious grease put on previously it was being pulled on so tight it didn’t want to come off.
We counted the links and chain needed to be about 105 links. Popped to Decathlon and for £9 got a 110 link one. Checked in store and it was the same width as the scrap chain.
New chain test fitted at end of video and comes on and off the sprocket easily.
It was a little long at 110 links so needed shortening by 3 links.
Once shortened we tensioned the chain using the adjustment on the flywheel. It’s a little trial and error but should have a small amount of vertical play in the middle.
Reassembled and tested and worked well. Time for a clean up and final check. Saved a £400 spin bike from the scrap for £9. Good days work.