For those of you who have increased your rear suspension travel, you may be finding that chain slack has become a real bother. If you try to stick with factory specs, your chain will be under tension before you are half way through the suspension travel. And if you have enough slack, the chain is flopping around and banging into the frame, swingarm, and whatever else it can reach. This has been my source of frustration for a while and I decided to do something about it before installing a new chain.
Some online research gave me some ideas for building my own spring loaded chain tensioner. The idea is not to eliminate chain adjustmets, rather to control the movement of the chain when there is more slack in it than the factory spec. I started with a MooseRacing chain roller as it was reasonably priced and large diameter which will have the chain running smoother over it. I then scrounged around my workshop and found some steel that I could fabricate into an arm. Some digging in the hardware bins provided a bolt with a nice shoulder to use as a pivot, some washers, and various springs.
After some time examining my Maxim, holding the roller in various spots, squinting, measuring, frowning, sketching and daydreaming, I had a plan. And the result is the following parts:
And when those parts are assembled, this is the result:
The keen eyed will notice the Kawasaki Ninja 250 suspension and linkages in the photos. The 5.1" of suspension travel is what has required me to have more slack in my chain than stock bikes. For the pivot point of the tensioner, I enlarged one of the screw holes that was for the sidestand safety switch. I also drilled a tiny hole for the top of the spring to hook into on the frame.
You may have also noticed that the chain has so much slack in it right now, taken up by the tensioner, that it is almost touching the bottom of the swingarm protector. As seen here:
Now, Once I get seated on the bike and the suspension settles some, there is about 1cm of clearance between the rubber protector on the swingarm and the chain. I anticipate having to adjust the chain slack some, and that I may need a different tension spring, as this is just the first attempt. But at least I can install my new (expensive) X-Ring chain when it arrives and not have to worry that I'm going to be stretching it or having it flopping around and rubbing on the frame.
I hope this give you some ideas and inspiration on how to modify your XS400!
Some online research gave me some ideas for building my own spring loaded chain tensioner. The idea is not to eliminate chain adjustmets, rather to control the movement of the chain when there is more slack in it than the factory spec. I started with a MooseRacing chain roller as it was reasonably priced and large diameter which will have the chain running smoother over it. I then scrounged around my workshop and found some steel that I could fabricate into an arm. Some digging in the hardware bins provided a bolt with a nice shoulder to use as a pivot, some washers, and various springs.
After some time examining my Maxim, holding the roller in various spots, squinting, measuring, frowning, sketching and daydreaming, I had a plan. And the result is the following parts:
And when those parts are assembled, this is the result:
The keen eyed will notice the Kawasaki Ninja 250 suspension and linkages in the photos. The 5.1" of suspension travel is what has required me to have more slack in my chain than stock bikes. For the pivot point of the tensioner, I enlarged one of the screw holes that was for the sidestand safety switch. I also drilled a tiny hole for the top of the spring to hook into on the frame.
You may have also noticed that the chain has so much slack in it right now, taken up by the tensioner, that it is almost touching the bottom of the swingarm protector. As seen here:
Now, Once I get seated on the bike and the suspension settles some, there is about 1cm of clearance between the rubber protector on the swingarm and the chain. I anticipate having to adjust the chain slack some, and that I may need a different tension spring, as this is just the first attempt. But at least I can install my new (expensive) X-Ring chain when it arrives and not have to worry that I'm going to be stretching it or having it flopping around and rubbing on the frame.
I hope this give you some ideas and inspiration on how to modify your XS400!
