need some help!

[t.c103]

I bought a secondhand Sofrider from Netherlands and relaly start getting used to it and like it more and more. Its a realy nice and funny format with the MBB and gives me a nice feeling that I´m in the bike and not just on the bike... something like a rollin extension of the body or something like that... My longest trip so far is a solo ride for 100 km with a average speed of 21 km... next step is to clip in the shoes and hopefully get some more speed.... Aiming for more legs and lungs and less weight on the engine aswell....
Now to the problem...
in about 36 ours from now I will join in my first social recumbent ride with the bike and its a trip of 130 km. and there will be some climbs.....The problem is that the chain is getting of the front ring on the inside when I go to the lowest gear as soon as I put some power on the pedals. I`m no expert on bikes and have no experience of cruzbikes so I went to the LBS for some help. Just left the bike there on my way to work an explained the problem but they couldn't even get the chain to fall of even if it happens for me every time I go to the lowest gear!
I have a single chainring in front and 8 gears on the cassette... So I guess I`m on my own to solve this before the ride and therefor I hope someone here on the forum will be able to give some advise...

I`m Swedish... sorry for the english

 

[1happyreader]

T.c103, your use of English is outstanding!
glad you like your sofrider
not much time, but here are my guesses.

bent chainring
bent derailleur hanger
needs new chain

 

[ratz]

If I read that correctly.

Chain Ring is single speed
Rear is an 8T

Under heaving load "aka pedaling up hill in low" the chain falls of to the inside.

I would concur with happy the things to check:

1. Chain is stretched and worn out; LBS should have the too to check that.
2. Front Chain Ring is bend
3. The Drive wheel is not mount square or all the way into the dropout.
4. Chain is too long
5. Rear derailleur isn't fully attached
6. Read derailleur hanger is bent or not securely mounted

 

[Charles.Plager]

Not a good solution, but you could add a front derailleur and fix it in place. It won't rub if the chain isn't falling off, and should prevent it from trying. You could also try something like NGear JumpStop.

Try getting a trainer and riding your bike to see if you can make it happen while stationary. Would make it easier for the LBS to diagnose.

 

[ratz]

Not a good solution, but you could add a front derailleur and fix it in place. It won't rub if the chain isn't falling off, and should prevent it from trying. You could also try something like NGear JumpStop.

Try getting a trainer and riding your bike to see if you can make it happen while stationary. Would make it easier for the LBS to diagnose.

Yeah and this would solve it too as a last resort. http://problemsolversbike.com/products/chainspy gotta think it's going to turn out to be something really simple.

 

[super slim]

You could set the bike up next to a wall, and get on the bike, with the front brake fully applied and try to pedal in first to 8th, to see what gear the chain drops off in.
Are any of the front chain ring teeth bent over from the bike falling over. If so carefully bend them straight again.
Do all Ratz's checks

Happy Cruzing!

 

[MrSteve]

You may have the original Sofrider, the V1.
The V1 had grey plastic chain guards mounted to the front chainring.
One chain guard was mounted on the inside of the chainring and the other
chain guard was mounted on the outside of the chainring.
These plastic chain guards were really effective at keeping the chain on the front chainring.

Here's how I know:
When I hit the neighbour's dog with my V1 Sofrider, the chainring bent and the
plastic chain guards were broken.
When I straightened the chainring, the chain would fly off when I rode over bumps.
To fix it, the bike needed new chain guards....
However, this was the excuse I needed to upgrade from the stock 8-speed
to a 24-speed, by replacing the stock single chain ring with a triple and a front deraileur.

Hope this helps.
Have fun!

 

[t.c103]

Hi

Thanks everyone for helping...

The LBS checked the condition of the chain and that was ok and they did not think that the chain was too long...
Nothing wrong with the attachment of derailleur that I can see... also checked that the wheel was in place...
The inner plastic chain guard was broken so I switched those so the broken one is on the outside now...
When I had the chain ring free I checked if it was bend it was not... well at least less than one mm ...
I have tighten all the screws in the front triangle so its not possible to adjust the boom anymore just by untight the screw on the boom. It might prevent the boom to flex when the birdlegs put some power on the pedals..

I did a very short testride and the chain is still in place...

probably because of the plastic chain guard and I don`t think that one will last for long.... hopefully it helps me this next ride...

Special thanks to Mr Steve for helping me find the excuse to upgrade

 

[t.c103]

Hi,

The social ride went fine, actually no problems with the bike.... but still, the problem with the gears might show up again so the only way to prevent this to happen is to upgrade, right!?
I will very much appreciate some advise how to do that... for example what parts that has been used by those of you that have experience of such a mod....


Kind regards!

 

[Doug Burton]

Check your derailleur cable housing. If it has a kink in it, and you feel a time delay between when you shift the shifter and when you hear the gears change, this can cause the chain to derail and fall to the inside on the chain ring. The "pent up" energy in the shifter cable can cause the derailleur to move very suddenly, and the chain can't move that fast. Some Sofriders suffered this due to the packaging they were shipped in. Replacing the short piece of cable housing between the fork and the derailleur can fix this.