Author Topic: APS front fender - pros & cons  (Read 3978 times)

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Offline sofadriver

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APS front fender - pros & cons
« on: January 01, 2015, 10:36:10 PM »
Although I've planned the new bike with a full (180 degree) front fender, I still have doubts about the value of it.

on paper;
It will make the body unit longer (good)
It will keep the top of the wheel from "throwing" air in the wrong direction (good)
If properly designed and in a perfect environment (wind tunnel) it should greatly enhance front aerodynamics (good)

in the real world;
It acts as a rudder and may cause wonky steering (bad)
It traps air (bad)
Steering is more affected by crosswinds (bad)

What are your views?
Mike in Tacoma

"aww, what the hell - let's just do it".............

Bike #833
100cc A/G, A/F and APS/G (in 2019)

Offline Frenchinjection

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Re: APS front fender - pros & cons
« Reply #1 on: January 02, 2015, 06:20:34 AM »
Our front fender is as close as allowed.  No issues so far at 157mph.  Going to fit race tyres next year so gap between tyre and fender will be bigger. www.saltbike775.co.uk  build links

Offline Stainless1

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Re: APS front fender - pros & cons
« Reply #2 on: January 02, 2015, 10:41:54 AM »
A properly designed full front fender will help move the air to the fairing with minimum disturbance. 
We did a test, as back to back runs as you can do at Bonneville, one with a standard Busa front fender on our 1000 and the next with a Busa fender I modified to meet the fender allowances for special construction.  The result was a 3 MPH gain... no we did not put the other fender back on to make sure it was the fender... this is LSR and the goal was to go fast and faster.
YMMV  :cheers:
Stainless
Red Hat 228.039, 2001, 65ci, Bockscar Lakester #1000 with a little N2O

Offline sofadriver

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Re: APS front fender - pros & cons
« Reply #3 on: January 02, 2015, 09:50:15 PM »
Well, I guess that pretty much settles it.
Thanks, guys.

Onwards!..............
Mike in Tacoma

"aww, what the hell - let's just do it".............

Bike #833
100cc A/G, A/F and APS/G (in 2019)

Offline sofadriver

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Re: APS front fender - pros & cons
« Reply #4 on: January 03, 2015, 01:56:37 AM »
Our front fender is as close as allowed.  No issues so far at 157mph.  Going to fit race tyres next year so gap between tyre and fender will be bigger. www.saltbike775.co.uk  build links

I checked your build pics but still can't figure the hardware you're using to mount the front fender. (I'm a little slow  :roll: )
Mike in Tacoma

"aww, what the hell - let's just do it".............

Bike #833
100cc A/G, A/F and APS/G (in 2019)

Offline JimL

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Re: APS front fender - pros & cons
« Reply #5 on: January 03, 2015, 10:01:07 PM »
PM sent

Offline Frenchinjection

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Re: APS front fender - pros & cons
« Reply #6 on: January 09, 2015, 12:26:41 PM »
Sofa.  I realised that there are not many pictures of the front forks.  The best I have is in the shipping images.  You can see 2 clamps on the lower part of the forks.  These are shaped to match the inside of the fender which screws on to them,  also the top of the fender screws onto the fork brace.  http://www.frenchinjection.com/Saltbike775/2013/Shipping/shipping5.html

Offline JimL

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Re: APS front fender - pros & cons
« Reply #7 on: January 09, 2015, 04:46:45 PM »
2 cents worth from the "been there, goofed" file:

- make that fender quick and easy to remove from the mounts that (should) stay on the forks to maintain position alignment.  When you are headed to impound after a sloppy salt turn out, you will be glad you thought this out.  Cleanng out that fender adds to your workload in impound, so make it simple.

- dont use stainless bolts threaded into aluminum parts.  They seem to lock solid in salt.  What started as a nice 6mm threaded hole on my FZR forks has eventually become an 8mm pass through for a bolt and nut.  Throwing away nuts and bolts is much better than throwing away fork lowers....that was a close call!

- anything mounted on the forks must be removed after the event and NOT left on over the year (this includes the axle) until you are certain it is cleaned and lubed well enough.  It is much nicer to find individual parts corroding in a box, than to find them mated to something expensive ......if you see what I mean.

Offline sofadriver

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Re: APS front fender - pros & cons
« Reply #8 on: January 09, 2015, 10:50:43 PM »
Sofa.  I realised that there are not many pictures of the front forks.  The best I have is in the shipping images.  You can see 2 clamps on the lower part of the forks.  These are shaped to match the inside of the fender which screws on to them,  also the top of the fender screws onto the fork brace.  http://www.frenchinjection.com/Saltbike775/2013/Shipping/shipping5.html


Thanks!
I've come up with something I think will work. I have axle pinch clamps on my forks which gives me some more options. I'll post pics when it's done (too hard to describe)
Mike in Tacoma

"aww, what the hell - let's just do it".............

Bike #833
100cc A/G, A/F and APS/G (in 2019)

Offline sofadriver

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Re: APS front fender - pros & cons
« Reply #9 on: January 09, 2015, 11:01:28 PM »
2 cents worth from the "been there, goofed" file:

- make that fender quick and easy to remove from the mounts that (should) stay on the forks to maintain position alignment.  When you are headed to impound after a sloppy salt turn out, you will be glad you thought this out.  Cleanng out that fender adds to your workload in impound, so make it simple.

Thank you for assuming I'm going to be in impound!  :-D :-D
That's good advice. Probably going to use dzus fasteners for easy removal.

Hadn't really thought about storing the bike after Speedweek. I have a friend who had major corrosion problems after storing his bike. I'm pretty experienced in corrosion control, though. For the past 12 years I've lived aboard my 40' cabin cruiser moored in salt water. I can tell stories!  :roll: :-)
Mike in Tacoma

"aww, what the hell - let's just do it".............

Bike #833
100cc A/G, A/F and APS/G (in 2019)