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squirl
06-15-08, 05:28 PM
Help!
Ive been commuting on my 2003 catrike speed for 6 months or so and it seems to ride fine and hasnt eaten up tires but I'm having some problems. When I took it out today and went down a long steep hill I couldnt keep the trike going straight, it just seemed to swerve all over the road when I hit around 35 mph, totally not safe to go any faster until I figure out the problem. I just had the wheels trued and tightened and they seem to be tight and straight. What am I missing? Also I am an experienced mt biker so I dont have some kind of death grip on the bars or anything like that, the trike just seems to dart back and forth across the road.

And should my but rest on the steering linkage under the seat? It doesnt seem to cause any problem but it just doesnt seem right. I tightened up the seat webing but I still rest on it. I lifted myself off the linkage while going 35 mph and it didnt seem to change the swerving.

thanks
jef

25hz
06-16-08, 07:30 AM
If your butt is resting on the tie rod, it wouldn't be surprising to find out you've bent it. Bending it will change your toe-in measurement and THAT will affect your steering. Your toe-in should be about 1/8", you need to make sure your tie rod is straight (or at least not bent any further) and you need to adjust things so that your butt does not rest on the tie rod.

Floyd
06-16-08, 07:57 AM
+1 on 25hz's answer,,,or at least that would be the next thing I would check. that is the first thing to look at on a 'motorized vehicle' when swerving is taking place.

squirl
06-16-08, 10:02 AM
I checked the toe in first and then for bearings for play. Ill recheck it. does anyone else have this problem with resting on the bar or do I /can I adjust somthing?
thanks
jef

Doug5150
06-16-08, 12:35 PM
When I took it out today and went down a long steep hill I couldnt keep the trike going straight, it just seemed to swerve all over the road when I hit around 35 mph, totally not safe to go any faster until I figure out the problem. ...
While checking it over mechanically is a real good idea, to a degree tadpole trikes all tend to have this problem and there is no fix. The front wheels' kingpin axis is not centered on the front wheels axis, and there will always be front-end flex that results in poor steering. The only exception to this would be a leaning tadpole trike that uses free-to-caster front wheels.

A delta trike (one wheel in front) will not have this problem, as there's only one steering wheel.
~

banerjek
06-16-08, 02:30 PM
If your butt is resting on the tie rod, it wouldn't be surprising to find out you've bent it. Bending it will change your toe-in measurement and THAT will affect your steering. Your toe-in should be about 1/8", you need to make sure your tie rod is straight (or at least not bent any further) and you need to adjust things so that your butt does not rest on the tie rod.
This was my reaction too.

However, how much experience do you have riding trikes and how do you stter? They don't handle the way a lot of people expect. Many people will pull on on lever while pushing the other. I find that at speed, this has a very destabilizing effect. When I'm moving down a hill, I just push gently with the opposite hand against the lever and let the other hand just follow.

mchell
06-16-08, 04:26 PM
For what it's worth, I would check out the "General Discussion" thread on this link.
http://catrike.yuku.com/
There's a wealth of info here that is Catrike specific. A phone call to tech support has also been helpful to me in the past. Good Luck!

Mike '06 "Road"

squirl
06-16-08, 08:59 PM
turned out that one of the tierod ends was loose and getting hung up. When I remeasured the toe-in I noticed that depending on how you turned while getting off the bike would give me dramatically different readings. It turned out that when the bolt was tightened and the tierod straightened out it was toed-in about an inch. Adjusted it and now the swerve is gone, 38mph going to the chiroprator and no swerve....sweeeeet.
Thanks and I will check out the catrike page.
jef