I just got a new Kent tandem last week. For some reason whenever we're starting out in low gear, it feels like the drivetrain is slipping. The chain isn't skipping, the cranks are still in sync, so I really don't know where to look. It seems like something is loose, but I don't know what. I can't seem to duplicate the issue when I'm off the bike, everything seems tight.

Ideas?

How many times has it done that?

One thought crossed my mind that it could be the freewheel tightening. If that's the case, after a time or two the problem will solve iteslf.

I was thinking maybe it was the freewheel tightening too... but why only from the stops? I was climbing a good size hill with my son not pedaling and my daughter in a trailer on the back and I didn't feel anything. But I pulled away from a stop sign last night and felt the same thing. All the other stops on the ride felt fine. It's been maybe 4 or 5 times that I've felt it.. after 4 or 5 revolutions on the pedal it seems to stop.

Count the # of teeth on the biggest cog in the back, and the # of teeth on the front cog that you are using. Post these numbers here. It may be the gear is so low it feels like it is slipping.

It really sounds like a derailleur adjustment problem to me.

Some questions:

Is is slipping on the front wheel or the rear cogs?

If rear - you say low gear - is this happening only on the lowest (largest) rear cog, or on others?

Was this a mail order bike?
If so, you will probably have to adjust both front and rear derailleurs. If you don't know how to do it, you'll have to learn or take it in somewhere.

My understanding is that Kent is mail order, and if so, I'd be willing to wager it's a simple adjustment issue.

The Kent is a WalMart offering. I have bopped around the bike trails with my kids on one and cuss it more often than not. I have built up a couple bikes with quality components that work like a dream. The Kent I can get to work for a little while, but it just doesn't have the quality of components to work right for more than a couple miles - and that was after swapping the front deraileur for a Shimano wide cage model, swapped the chain for a lower end Shimano and dumped the Falcon Freewheel for the now discontinued Shimano 11-34 7 speed. Bottom line is if you want it for cruizing around the neighborhood and don't care if it doesn't work quite -right you will be fine. Just don't expect it to work like a bike shop bike.

The cogs aren't slipping as far as I can tell. I don't hear any skipping. It feels like the cranks are moving independent of the chain, but everything is still in sync so that doesn't seem to be it. The other speculation is that the freewheel was tightening, but it doesn't make sense that it would have done that as much as is has.

This happens on the largest rear cog. I don't know if it happens on the others because it doesn't do it every time, and most of the time I'm starting on the largest cog since I have my son who may or may not be pedaling and a trailer in the back. I'm on the middle ring in the front.

Yes, this is mail order. I think the rear derailleur is bent because no amount of adjustment is getting it to shift right every time. I'll get it right on the downshifts, but then the upshifts don't work. I've been working on dialing it in when we stop on rides, but I haven't had time since we started riding it to take some time at home to look at it in detail.

If I determine there's nothing wrong with it, I perfectly willing to accept the current functionality until I have money to upgrade the components. This was an experiment and I didn't want to spend a lot of money on a bike out of the gate. The frame is pretty nice and I don't mind swapping out the components in a few years to get it to work better once I proves the interest lasts. Or trade up to a nice tandem.

First check chains for any tight links or kinks every link look good by taking each and see if its tight first may be as simple as that check this first also chain tension on both main and timing rings.
If it looks good check hub, get the wheel off ground spin wheel how do the ratchets sound smooth and even you might try spraying some lube into it even if it does sound good.
Kent tandem don't know were you picked it up from but it may need some fine tuning and adjustments and if it came from a chain store out of the box they just slap them together and sell.
Those department store bikes should be gone thru when built up to insure everything is good to go.

Well, I ordered it from Amazon and put it together myself. You guys are starting to give me a complex about my ability to assemble a bike. I'll check on everyones suggestions sometime.. having some family issues now so it may be a few days before I get around to it again.

LOL no worry just check everything over carefully first then if you still have problem dig deeper into it but check things over first even if you fill all is good sometimes its just something over looked.

Well, after getting the freewheel replaced on my other bike, this is exactly what I was feeling on the tandem. Don't know why it took so long to tighten down.. but last trip it didn't do it at all, so it seems to finally be tight.