Chain Jump

[Nealh]

Gear indexing/derailleur adjustment needed.

 

[saneagle]

This will probably sound daft, but nobody has mentioned it, so here goes:
Sometimes, when in top gear (9th), and riding up an incline, using the second level of assistance, the chain seems to slip momentarily, but then recover. Not a major problem unless you are standing on the pedals (which I don't usually do). Doesn't seem to do it on any of the other gears. It is just possible that I am working it a little too hard, and need to change down a gear, but this happens even when I have a fair bit of momentum built up. I'm not trying to climb a hill in top gear from a standing start.
Before I had an e-bike I'm sure I have been told that chains will stretch over time. I think it's more that the holes in the links get worn down, which makes the chain a bit sloppy. I thought (wrongly?) that one solution was to simply remove a couple of links from the chain. Is this a good idea?
I'm talking about a bike with a rear derailleur. Probably not a good idea on a bike with hub gears.
My bike is a Trek Allant +5, a hard tail hybrid with mountain bike aspirations.

When you slip in top gear, it's probably because the chain is too long. You might be able to get a bit more tension by adjusting the "B" screw.

 

[Benjahmin]

Climbing a hill in 9th gear is never a good idea. The extra strain on you and your bike is very damaging. Your knees and ankles will suffer from the lower cadence, better to change down (as you would when driving a car) so your cadence is higher.
Also, as I think your bike is a mid drive, you are putting a lot of strain on the motor in too high a gear and risk burning it out.

 

[Peter.Bridge]

I used this to size my chain

Chain Length Sizing

This repair help article will take you step by step through the different methods of sizing a bike chain for your drivetrain.

www.parktool.com

A new chain quite often slips, mine started off slipping on the 11t cog but after 50-60 miles was ok. As has been said, adjusting the "B" screw to "wrap round" the cog a bit more helped with mine too.

 

[Saracen]

I have said it many times but once again

For info whenever you replace a part DO BOTH

When replacing a chain also replace the cassette

When replacing a cassette replace the chain

 

[saneagle]

I have said it many times but once again

For info whenever you replace a part DO BOTH

When replacing a chain also replace the cassette

When replacing a cassette replace the chain

That's not necessary, so a waste of money. All you need is correct adjustment.