05-21-2008, 12:37 PM | #1 |
Join Date: Jan 2007
Location: Northern Vermont, USA
Posts: 1,247
|
My new trunk and the high speed stability issue.
Just installed my new trunk last night. Got to take the bike for a test ride today and at speeds above 45 mph, the rear of the bike is borderline dangerous. It feels like you are running close behind a truck in the air wake, but there's no truck! I have seen several posts here lately about stability issues. For my bike the trunk really messes up the aero. Luckily it's a quick release style (30 seconds on and off), and I will only be using it for trips to the grocery store once in a while.
__________________
First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP! |
|
05-21-2008, 01:30 PM | #2 |
Join Date: Jan 2008
Location: Sk, Canada
Posts: 68
|
make sure your rear tire is lined up to the front
|
|
05-21-2008, 01:41 PM | #3 | |
Join Date: Jan 2007
Location: Northern Vermont, USA
Posts: 1,247
|
Quote:
__________________
First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP! |
|
|
05-21-2008, 01:46 PM | #4 |
Join Date: May 2008
Posts: 527
|
Looks good,
I do like the trunk and the fact that it is a quick release really makes it a handy item to have. can you tell me where you got it from? and it it big enugh to put a helmet inside? Thanks
__________________
ALONZO 2007 Lifan a.k.a lucy lu. 2,000 miles of good riding. |
|
05-21-2008, 02:15 PM | #5 |
Join Date: May 2007
Location: Altamont, Kansas
Posts: 15,103
|
I have no troubles related to my trunk unless I load it down with heavy items. I even strapped a little tykes plastic slide to it and crusied a 55mph home. I got some looks.
Maybe you need to add a spoiler to the lid for more downforce. 8O Allen
__________________
You meet the nicest people on a Honda Clone. |
|
05-21-2008, 02:46 PM | #6 |
Join Date: Sep 2006
Location: COLUMBIA, SC
Posts: 973
|
Interesting. I haven't had any major issues, but mine isn't as "tall" as your's appears to be. One thought though, could you mount it in reverse. It appears to be more aerodynamic the other way.
__________________
2008 Jonway MC-70-150 2007 Roketa DB-07B (RSM-200E) 2006 Roketa DB-07A (RSX-200E) 1995 Kawasaki Concours (ZG1000) |
|
05-21-2008, 02:50 PM | #7 |
Join Date: Jul 2007
Location: Independence,Missouri
Posts: 1,049
|
Whats weird is that the box isn't that wide.You would think the box would be sheided by the rider for the most part.
__________________
Kman 2007 HI-BIRD 250 2007 Vbike V4S 250 |
|
05-21-2008, 04:53 PM | #8 |
Join Date: Feb 2008
Posts: 392
|
Yeah.maybe you could position it different so it is easier to handle?
Either that or tie on the back of the seat :wink: |
|
05-21-2008, 07:57 PM | #9 |
Join Date: Jan 2007
Location: Northern Vermont, USA
Posts: 1,247
|
I bought the trunk on eBay. It was a scooter take-off. Bolted right on, and is definately narrower then my body is, but it IS the cause of the aero instability. I pulled it off tonight and the wiggle is gone. I'm not worried about it forcing me off the road or anything, it is just not as planted in the rear as it was. Doesn't begin to wiggle until I am up to roadway speed. Just thought I would throw that out there as info. BTW, my bike is still getting 80 - 90 + mpg. Not bragging or boasting, but the fill-up today was right at 92 mpg. Mileage verified accurate. Amazing.
__________________
First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP! |
|
05-22-2008, 08:57 AM | #10 |
Join Date: Sep 2006
Location: COLUMBIA, SC
Posts: 973
|
Awesome! I know Dad said he's gotten over 80 several times, but I just calked it up to Dad math Then too, I do weigh 250lbs and he's only 180lbs...So me getting 75mpg is pretty good.
__________________
2008 Jonway MC-70-150 2007 Roketa DB-07B (RSM-200E) 2006 Roketa DB-07A (RSX-200E) 1995 Kawasaki Concours (ZG1000) |
|
05-22-2008, 10:11 AM | #11 |
Join Date: Apr 2008
Location: Blue Springs, Missouri. United States
Posts: 505
|
I don't know if these bikes have adjustable suspension, but on my sportbike I would have the same problem (at real high speeds) when I put on the saddlebags and roll bags and like you, it was aerodynamics not the weight that caused the problem. The drag pulling on the rear of the bike would make the front loose, so I clicked one on the preload, front and back, then barely increased the compression and rebound. I'm not a suspension tech, but it did smooth it out and that was without a steering damper. I thought I saw where you put an R-1 shock on, that's pretty interesting. Good luck, thanks for the info.
|
|
05-22-2008, 12:12 PM | #12 | |
Join Date: Jan 2007
Location: Northern Vermont, USA
Posts: 1,247
|
Quote:
__________________
First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP! |
|
|
05-22-2008, 09:41 PM | #13 |
Join Date: Jan 2007
Location: Bradenton, Florida
Posts: 1,200
|
Red,
I thought you were a physics major or something??? Didn't you custom build your own scissor shock linkage/ R1 shock/ 105 inches of travel or something of the sort??? Just messing with you bro, when I ride 2 up I feel a big difference in handling but I guess that's true for anybike.. Do you notice it when the carrier is full/has weight or is it the same when it's empty? As far as aerodynamics I'd think your body would block most of the wind flow, I'm sure you'll figure it out...
__________________
06 Lifan 200 GY-5 |
|
05-23-2008, 08:21 AM | #14 | |
Join Date: Jan 2007
Location: Northern Vermont, USA
Posts: 1,247
|
Quote:
__________________
First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP! |
|
|
|
|
|
|