My son and I just finished installing a Motorvation Spyder on my Valk and I took my first drive today (ever).
I read all that I could on sidecaring so most of what I experienced today was expected. However, one question. I kept the speed under 30mph and the rig runs straight on steady throttle. However there is a tendency to "bump steer" on irregularities in the road. There is no steering damper. Almost a wobble but not quite. I have no idea if this is normal. The steering head bearings have no play but the steering turns almost too easily when off the floor. Also I'm running the normal tire pressures for a solo bike, 38 frt, 44 back. Sidecar air pressure is 35psi. I'm thinking of tightening up the steering head bearings just a tad and lowering the front tire pressure. Comments?
I haven't experienced bump steer unless there was a damper installed.
It might help to tighten up the head bearings so you eliminate the flop.
A little resistance helps. Just don't tighten too much to avoid spalling the bearings.
Tire pressure usually stays the same on the front wheel, solo or hacked.
One might raise it for a lot of twisties work for more sidewall resistance and less tendency to squirm. Rear tire pressure is usually raised a bit for two up riding or hack work. This helps for loading and sidewall resistance.
Lonnie
Along with what Hack'n said you may want to check the lead of the sidecar wheel. I personally tend to run more lead than many and if the bike suspension is soft and the sidecar suspension is fairly stiff you can get an effect that is simialr to bump steer. As the sidecar wheel hits a hole it make the rear of the bike squat which can create a rocking type motion that feels like bump steer. The greater the lead the more this may be evident. If you are running a lot of toe in it aggrivates it even more.
You may want to call Motorvation and get their input too. They are very good at answering these type of questions.
Please keep us posted as thsi type of thread may help many other folks out there too.
Oh, and welcoem to the world of sidecars 🙂
besides the good advice given above, drop the sidecar tire pressure to about 24-25 pounds, no need for more there.35 is awful high
.
Thanks to everyone for your very helpful suggestions.
I'm going to recheck the toein. I now have metal straightedges. I will probably tighten up the steering head just a little too.
As for tire pressures, I'm a little concerned about running lower pressure on the sidecar tire. The Valk is an 800 pound bike and I'm wondering about the side forces against the sidecar tire could break the bead loose on the tubeless tire.
As far as lead, as near as I can tell, I'n running 14 to 16 inches of lead and I couldn't get any less since the Spyder's wheel is almost in the center of the car. Gary of Motorvation confirms that will be the case.
The twitchiness appears to be only side to side movement no up and down.
Overall, I'm most certainly glad to have read up about all this in literature from Doug Bingham, Hal Kendall, Dave Hough, and others. This has been a learning experience with a steep curve but I'm already enjoying the ability to turn around in the street and not having to hold up an 800 pound Valkyrie with my 78 1/2 year old untrustworthy knees. Thanks to everyone. i'll be asking more questions as I go. I'm a retired engineer so I have to know, LOL.
Originally written by solo1 on 10/19/2006 7:44 AM
Thanks to everyone for your very helpful suggestions.
I'm going to recheck the toein. I now have metal straightedges. I will probably tighten up the steering head just a little too.
As for tire pressures, I'm a little concerned about running lower pressure on the sidecar tire. The Valk is an 800 pound bike and I'm wondering about the side forces against the sidecar tire could break the bead loose on the tubeless tire.
As far as lead, as near as I can tell, I'n running 14 to 16 inches of lead and I couldn't get any less since the Spyder's wheel is almost in the center of the car. Gary of Motorvation confirms that will be the case.
The twitchiness appears to be only side to side movement no up and down.
Overall, I'm most certainly glad to have read up about all this in literature from Doug Bingham, Hal Kendall, Dave Hough, and others. This has been a learning experience with a steep curve but I'm already enjoying the ability to turn around in the street and not having to hold up an 800 pound Valkyrie with my 78 1/2 year old untrustworthy knees. Thanks to everyone. i'll be asking more questions as I go. I'm a retired engineer so I have to know, LOL.
dont worry about the side pressure on the SC tire. the tire will slide before it develops enough force to come off the rim.
remember, autos run the tires at 28-30 pounds with a 3-4000 pound car or truck on them!
most sc rigs run with the 24-26 pound settings on the SC, with bike tires OR auto tires.
oh yeah! welcome to the SC world! you have been bitten!!!!
ask away!
