167LikesTamiya XV-01
09-05-2016, 12:02 PM
#946
Tech Addict
Droop droop droop
I think I found it now. No really, why my steering was so unbalanced with the durning on power exit, yeah the battery weight was a MAJOR factor in reducing the spin out.
But the biggest helper, was adjusting the droop screw on the one side. The side I was turning (left) would always spin out much easier than the right. I noticed that the inner wheel was spinning more (lifting), which means all the weight was on the outer wheel. When that outer wheel breaks lose, you have instant rear end spin out. So I lowered that inside wheel just a little, (tightening the droop screw) and bam! Now both wheels have traction when power on exiting. I cannot believe how much of a difference droop makes!
I can now swing side to side and because the rear wheels don't lift as much during weight transfer, the car is predictable and I no longer need to compensate for one side's oversteer.
But the biggest helper, was adjusting the droop screw on the one side. The side I was turning (left) would always spin out much easier than the right. I noticed that the inner wheel was spinning more (lifting), which means all the weight was on the outer wheel. When that outer wheel breaks lose, you have instant rear end spin out. So I lowered that inside wheel just a little, (tightening the droop screw) and bam! Now both wheels have traction when power on exiting. I cannot believe how much of a difference droop makes!
I can now swing side to side and because the rear wheels don't lift as much during weight transfer, the car is predictable and I no longer need to compensate for one side's oversteer.
09-05-2016, 01:06 PM
#947
Tech Addict
Damper Angle
I am so very pleased that my car is now consistent when doing hard turns. I think this even helped with the premature wearing of inner front tires, circle of death, yeah it still happens, but I think a little less.
Anyway, I was playing around with damper angles, which actually lead to my droop screw discovery.
Before the droop screws, I actually set my rear dampers to a more vertical position. This made the rear dampers feel a little more linear.
I just took some pictures to show some of the available variations afforded by the xv-01.
So far, I prefer a more upright position in the rear. I think if the car's rear was heavy, more damper angle rear would be useful.
Anyway, I was playing around with damper angles, which actually lead to my droop screw discovery.
Before the droop screws, I actually set my rear dampers to a more vertical position. This made the rear dampers feel a little more linear.
I just took some pictures to show some of the available variations afforded by the xv-01.
So far, I prefer a more upright position in the rear. I think if the car's rear was heavy, more damper angle rear would be useful.
Last edited by 4roller; 09-05-2016 at 01:18 PM.
09-06-2016, 10:33 AM
#950
Tech Addict
09-06-2016, 12:56 PM
#951
09-06-2016, 10:11 PM
#953
Tech Addict
Wow so much off-road fun from firefoxussr and bvrc!
Meanwhile in on-road land (I should have got the TC right?) I got some new gearing.
72T Jconcspts silent spur, and Robinson Racing 38T pinion.
Side by side with my previous gearing (which was awesome) 77/32
Before and after, nothing sexy here. In fact, the pinion is too big to use a normal sized screw driver to tighten the motor screws, I had to set the mesh, remove the pinion to tighten the screws, then re apply the pinion.
The new gearing sounds a lot more luggy. When coasting, it doesn't sound as nice as the previous gears. I checked the mesh twice, it's fine. It's just that the new ratio seems to push the motor rotor poles at a different pace than the other set. The things we sacrifice for speed, right? I can already tell it's faster, in my little backyard concrete area where I test the car. When I have some time I'll bring it out to the street for a speed run.
I look at the size of this pinion and scoff, "on roaders." Back in my off-road days, we'd be pushing it if we went over 27T, and that was really big!
Meanwhile in on-road land (I should have got the TC right?) I got some new gearing.
72T Jconcspts silent spur, and Robinson Racing 38T pinion.
Side by side with my previous gearing (which was awesome) 77/32
Before and after, nothing sexy here. In fact, the pinion is too big to use a normal sized screw driver to tighten the motor screws, I had to set the mesh, remove the pinion to tighten the screws, then re apply the pinion.
The new gearing sounds a lot more luggy. When coasting, it doesn't sound as nice as the previous gears. I checked the mesh twice, it's fine. It's just that the new ratio seems to push the motor rotor poles at a different pace than the other set. The things we sacrifice for speed, right? I can already tell it's faster, in my little backyard concrete area where I test the car. When I have some time I'll bring it out to the street for a speed run.
I look at the size of this pinion and scoff, "on roaders." Back in my off-road days, we'd be pushing it if we went over 27T, and that was really big!
09-07-2016, 01:19 AM
#954
If you think that gearing is high, check this out:
That's the 40/65 gearing on my XV-01 FF. I had to figure out how to fit a non-slipper spur gear into the slipper clutch so I could still control the maximum torque delivered to the front wheels.
Of course, then there's the 40/55 gearing in my TB-04R, but that's a very different kind of touring car:
That's the 40/65 gearing on my XV-01 FF. I had to figure out how to fit a non-slipper spur gear into the slipper clutch so I could still control the maximum torque delivered to the front wheels.
Of course, then there's the 40/55 gearing in my TB-04R, but that's a very different kind of touring car:
Last edited by fyrstormer; 03-29-2018 at 04:32 PM.
09-07-2016, 07:26 AM
#955
Tech Addict
If you think that gearing is high, check this out:
That's the 40/65 gearing on my XV-01 FF. I had to figure out how to fit a non-slipper spur gear into the slipper clutch so I could still control the maximum torque delivered to the front wheels.
Of course, then there's the 40/55 gearing in my TB-04R, but that's a very different kind of touring car:
That's the 40/65 gearing on my XV-01 FF. I had to figure out how to fit a non-slipper spur gear into the slipper clutch so I could still control the maximum torque delivered to the front wheels.
Of course, then there's the 40/55 gearing in my TB-04R, but that's a very different kind of touring car:
I think if I ever want to goto a lower FDR, then I'll have to either switch back out to the non slipper (nah) or come up with a solution like yours.
Having direct power (like stock) seems a little dangerous for the drivetrain. After I installed the new gears, I locked my slipper, and found my belt was clicking. The last thing I want is a worn out belt. So I immediately tightened it up. I also added a washer to the belt tensioner, moving it out slightly, so that both belt roller bearings would engage evenly.
No slipper seems like too much torque. How do other TC's like the TA, TB and TRF chassis handle this torquey businesses?
09-07-2016, 10:54 PM
#959
Driver discipline. Touring cars are generally built for racing even if they're not actually used that way by most owners, so it's assumed by the designers that the drivers will learn how to ease into the throttle to avoid overloading the drivetrain. Also, for racing purposes the reduction in rotating mass is considered a good tradeoff for having no slipper clutch. Also, belt-driven touring cars generally have larger pulleys on the front and rear diffs, hence more contact area for the belts to grip. Shaft-driven touring cars can get away with not having slipper clutches because there isn't anything to stretch or break, as long as the wheels don't get jammed, which is very unlikely when driving on-road.
09-08-2016, 06:13 AM
#960
Tech Addict