Bigger front chain ring (FastRoad E+ EX 2021)

[Kondekka]

Hey!
Was wondering where to search bigger chain rings, availability is very poor locally in Finland.
I'm also quite new to bike hardware and parts so I don't know which front chainring would fit in my bike.
I know it's fitted on 4 screws and that the original chainring size is 42, id like to go for 48 to 52~ish sizes, the prices for some models are ridiculous
and I wouldn't like to risk buying 150$ chainring that doesn't fit.
Any recommendations for retailers around EU and some help for finding proper chain rings would be greatly appreciated!
Oh and also, if I buy a bigger chainring, does it mean that I would have to replace the existing chain as well?

Thanks

 

[JRA]

You have a 104 bcd chainring. Amazon is everywhere! And yes you will need a longer chain. Here is a suggestion also

https://www.amazon.com/DECKAS-104BCD-Narrow-Chainring-11-Speed/dp/B08521J7JX

Amazon.com : KMC X11 , Silver/Black 118 Link 11 Speed Chain : Sports & Outdoors

Amazon.com : KMC X11 , Silver/Black 118 Link 11 Speed Chain : Sports & Outdoors

www.amazon.com

 

[Kondekka]

Thanks JRA! That looks good, and affordable!

 

[Stefan Mikes]

118 chain links would do? How many are there in your existing chain @Kondekka?
The second matter is: will the large chainring fit your frame? Because I doubt it. The 48T, 104 BCD Decka's chainring has the outer diameter of 203 mm. Use a tape ruler and check if the big chainring would not hit the chainstay before you spend your money... (It is very easy to give advice without seeing the e-bike).

More than 102 mm?

 

[Kondekka]

I haven't checked how many links I have, manufacturer lists that the product originally has 122 links, I think it's less than that after installation though.
I do need to make sure that I have room in the frame for the chain ring. I'll make sure to do that soon. Thanks for pointing this out @Stefan Mikes.

 

[Stefan Mikes]

I haven't checked how many links I have, manufacturer lists that the product originally has 122 links, I think it's less than that after installation though.

If you increase the chainring size from 42 to 48T (if doable), you need to increase the number of chain links with 6. It means you will need a 11-speed, and probably 138 links expensive e-bike chain, and shorten it to the proper length.

 

[Kondekka]

I've been busy lately, but I did check the bike... Not looking good, there's probably 1-1,5cm of space for the chainring. I would have to start hammering the frame to fit a bigger one.
@Stefan Mikes thanks for saving my ass again ... I'll have to re-think my plans. I probably have to give up the idea completely.

 

[funnel]

If you increase the chainring size from 42 to 48T (if doable), you need to increase the number of chain links with 6. It means you will need a 11-speed, and probably 138 links expensive e-bike chain, and shorten it to the proper length.

Actually if he buys a +6T chainring he needs a +3 links longer chain because the chain travels only on half of the chainring all the time. So a 2 links or 4 links longer chain since you can't do 3.

 

[tomjasz]

On some drives moving up to a larger chainring stresses the motor and they gain dangerously higher heat. Not so with Boasch, Yamaha, and the similar?

 

[Stefan Mikes]

On some drives moving up to a larger chainring stresses the motor and they gain dangerously higher heat. Not so with Boasch, Yamaha, and the similar?

I was riding my Vado with a large (stock) 48T chainring, then swapped to a 38T one. No difference in temperature readouts for the motor or battery.

 

[johnkora]

Why do you need a larger chain ring my fastroad is derestricted and I can go 50kph easily

 

[Kondekka]

Why do you need a larger chain ring my fastroad is derestricted and I can go 50kph easily

Just for fun, but it's pointless now. My bike got stolen.
Looking to buy a Haibike this time around and try out the Bosch Performance CX Gen 4 engine and it's capabilities.
I loved the Syncdrive Pro, although my engine had a creaking problem and should've been repaired.
I have some enjoyment from knowing that the thiefs got a bike that I haven't serviced, they don't have the keys for the battery, no charger and the motor should've been replaced or repaired.

Just a friendly reminder, keep your bike locked even if you stop by somewhere quickly, get an Airtag or SmartTag for your bike. Ebike thefts in my country have gone through the roof, just yesterday some crackheads had stolen 150k worth of ebikes from a bike shop...
I bought an SmartTag+ and it's going to go into the new bike when I get it.

 

[johnkora]

Thanks JRA! That looks good, and affordable!

Why do you need a bigger chainring I have a fastroad e plus 2 2020 and I can get to 50kph no problem (unrestricted)which is too fast I feel cruising alone at 35 to 40 is perfect the 25kph cut out is a joke and ruins a wonderful bike.