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Tandem; synchronizing chain on drive side

Sometimes I want the synchronizing chain on the drive side of the bike.
More than one mid drive motor will only accept a synchronizing chain on the drive/right side of the tandem.
I think this is a useful feature because Bikecad offers the possibility to create asymmetric chainstays

Question: I could not figure out how to make the synchronizing chain visible in the design.

Synchronizing chain

Displaying chains (and/ or rear derailleurs) in BikeCAD can really slow down the performance of the program. Therefore, I usually encourage people not to show the chain or derailleur until the design is finalized and turn it off again before making any significant revisions. This being the case, when I considered the option of showing a synchronizing chain which I knew would slow things down even more, I elected to direct my efforts to other tasks instead. This is something I might revisit in the future, especially if others are also interested in this.

  Yes, I have noticed the

  Yes, I have noticed the chain requires a lot of computerpower.
I want to ask: Why did you choose not to show the number of links when the chain is not visible?

I will explain why the number of links of the Synchronizing chain is important for me to know.
The length of the Boom tube is primarely determined by the bodyposture of the stoker rider.
Then you choose the size of the chain rings for the Synchronizing chain.
It is important that the Synchronizing chain has only a littlebit slack when it is still brand new.
So you have to use the Excentric solely only to compensate for the wear of the chain.

Often you only have to make the Boom tube just 5 mm longer to take away too much slack.

When you start with to much slack in a new chain, the Excentric cannot compensate for slack any more.
And you will have to mount half a link. Which is not an ideal solution.


For the moment I have created a special bike (only a chainstay) with only a sprocket 34T and a driver chain ring 34T for the calculation of the ideal combination of Boom tube length and Synchronization chain ring.
I think life would be easier if I could do this calculation within one file.

Tandem chain

Thanks for the feedback. I don't show the number of links when the chain is not visible because calculating the number of links is part of the same computationally intensive process used to determine the path of the chain.

I will plan to account for the timing chain in a future update.

Thank you.

Thank you.

Today I found an easy calculation to define the minimum required length of the Boom tube for a synchronizing chain without slack.

When the Boom tube is exactly xx.0000000 inches, the synchronizing chain will be exactly tensioned.
Regardless of the size of the chain ring.

I think people who design in inches will never have met this problem.
But mm oriented people should choose the length of their Boom tube to be a multiple of 25.40000 mm

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