Simplex 5 speed build

[pd]

Pete SOCAL Motor Bicycle Racing is the group I 'kinda follow, nice tracks, good participation and organized structured events and classes. Many of the bikes are pretty awesome with qualified riders some pretty fast racing in the top classes. You might want to give them a look see. I just like racing but don't intend to actually get out there and mix it up. I'd probably be the beaver on the track & get out in the middle of the course and dam things up! Rick C.
 

Hmm , I wrote a reply a couple days ago , but it isn't here anymore . Maybe yesterday's server problem had something to do with that .

Anyway , I couldn't find a specific site for SoCal MBR , other than Facebook . Still , looks like some pretty serious work being done . Interesting .
And , I don't intend 'mixing it up' anymore either . Been there and done that . My reaction time isn't exactly what it was when I was invincible .

Pete .

[ndian22]

Facebook is also what I have on them Pete.

[ndian22]

I turned the V-twin predator over to my Harley guy to build out. He's good so that means he's always covered up in work. How long? It's a start. I'll be very satisfied with 30 dependable hp. & a valve train that will hold up once the rev limiter is removed.

I'm making a template of the engine and battery box profile to size the frame with. I'm guessing 63" but want to be certain. I'll be going with a double tube frame design and low profile. I'll use 17" - 36 spoke wheels both stainless and DOT rated, discs front, rear and on the sidecar. S rated (110 mph) tires 3" wide rear and 2.25" front & side car. The overall tire height inflated is right at 25" for the rear & 24" on the front. I plan on having 3.5" ground clearance on both bike and sidecar. Target weight of the bike 220 lbs. with sidecar at 75 lbs.

As I posted earlier I won't mimic the Simplex frame lines though I'd like to. It's just a size & space thing. To house the V-twin and keep proportions correct the bike would be not only extremely long but tall as well. Space requirements for the V dictate top tubes and bottom tubes be parallel to each other as well as the ground.

Swing axle may be used in a covert fashion.  Rick C.


 

[pd]

Sounds interesting , Rick .

Please , keep us posted .

Pete .

[Reggie LeGros]

Your bike looks great.  You are a very talented dude

[ndian22]

Thanks Reggie. Your list of restores is quite impressive as well. A quality build "to factory" spec, in my experience, is more time consuming and expensive than are my current and past flights of fantasies. I of course am interested not only in all things Simplex but also the James bikes as well. Though I'm certainly not an authority concerning either. Updated photos of past builds and of course your current Simplex conversion would be a treat for us all.  Rick C.

[ndian22]

Putting parts together for the V-twin build & riding some everyday the Simplex Cooper Gator is proving very reliable transport, but the fun factor is off the charts. Photos as I get around to sizeing.

[ndian22]

Update on the V-twin soft tail build. Swing arm frame & components are placed & sized. Shock will be 10.5" spring over air (not pictured) bicycle bottom bracket components are used for swing arm pivot. Forks shown will be widened 1.5" to clear 160 mm disc rotor. Wheels are DOT compliant 17" & tires speed & load rated. 12 mm & 14 mm titanium axle bolts will be used. Custom hub adapter & rotor adapter secure & locate the 160 mm rear rotor. Next step will be to add gussets & lengthen the horizontal drops to the swing arm assembly. Then it's on to the motor & sidecar mount assembly.

Still think about 60" or so wheelbase to house either of my V twin engines. Rick C.   

[ndian22]

Some progress on my v twin build. Rear swing arm about 75% complete & front forks even closer. Everything in between not even started. The rear triangle is a fat tire frame cast off...with mods, but sizing was about perfect. Most of the fasteners will be replaced with proper strength hardware once exact lengths are determined.

Front forks have been widened from 4" to 5.5" to allow fitment of disk brake rotor hub. It can mount dual rotors but I think one will be enough? Can easily add another. 

Rather than use a jig to hold everything in place while getting everything in it's proper placement I'm using the fat tire bike frame. The rear triangle is the only part of the fat tire bike to be used in the final frame. I'm still thinking wheelbase will be just under 59".

 Rick C.

[pd]

Looking good , Rick .

What is the diameter and thickness of the rotors you're using ?

Pete .

[ndian22]

Thanks & hope you're enjoying the sunshine out in Az. man I feel for the guys up N. right now 'cause we've had wind chills at -17 for a couple of days here, but without the snow & I hated it!

Rotors are S-Ram Avid regular 160 mm mountain bike rotors 1/16" thick. The calipers are also Avid and are mechanical. I've used these on many bikes over the last 20 years on both motorized and pedal bikes without a single failure. So it's what I trust. I run the same setup on the front wheel of my 170 lb. Simplex tribute bike & it used alone is adequate for my stopping  requirements on that ride. I use the Archer drum on the front of the Harley tribute & always use both front and back to stop confidently from speeds over 25 mph or so.

The hub I laced up on the front of my current build has rotor mounts on both sides so I can if needed run a dual brake up front & by widening the forks I now could run 180 mm to 220 mm rotors as well, but doubt that will be necessary even with the added weight of the sidecar, which will also run the Avid brake setup which will be operated by a foot lever mounted on the sidecar frame. 

I haven't completely ruled out a sidecar mount design to switch the car from the V twin bike to my Simplex 5 speed either. Still having fun just doing it slower.  Rick C.   

[pd]

We definitely struck it rich for sunshine and warm temps . High 30s to mid 40s at night makes for good sleeping and low to mid 70s during the day is shorts weather . Winds are light or none . I ride daily .
Another week before we head to Yuma . The temps are even nicer there by 5 to 10° .

I asked about the rotors because I'm thinking about a front disc on the Simplex , but , it has to run decent first .

Anyway , thanks for sharing . I have a little more food for thought .

Pete .

[ndian22]

I've been changing things up on some old bike builds and forks seem to be what needed changing. I found a set of Harley style four spring forks that suited me, they have quite a bit of classic details and actually ride very nice. They are 1" threaded steer tube & are constructed of 3/16" plate steel & .125" wall tube & will clear a 3" x 26" bicycle tire. I'd say plenty stout enough for a Simplex weight or small cycle build.  Rick C.

[pd]

Nice fork , Rick .

Don't even need a headlight , as shiny as those springs are .

Pete .

[ndian22]

Thanks Pete as shiny as the springs are the fabricator included on the top leg and steer tube plate a nice place to bolt a head lamp to. I wish they had been as helpful by including a sturdy fender brace bracket under the crown brace, but I can probably figure it out.

I have a study set of un-sprung Indian style girder forks scheduled for arrival today. I plan on mounting those to my Grubee bike frame. If they are built as strong as they look I'll buy another set to use for a leaf spring fork I've been putting off building for some time now.  The V twin build is awaiting my finishing the torpedo style tank to a point of proceeding with the main frame.   Rick C.