Service Department             Call  540-298-9310
Here at the SuperXparts shop, we  work on Excelsior Henderson motorcycles exclusively.  For over twenty years we have concentrated on  these fine machines and know them well. 

Our objective has always been to keep the Super X on the road and ridden regularly.  Jamie is our only tech, so you can be certain your concerns are listened to and heard.  We price service work fairly at $100.00 per hour, basing  time on our extensive  experience and a time clock.  We can provide accurate estimates for any work you need.  We only like pleasant surprises and think you probably do too.  Of course, stuff happens, but you can be sure to get a call so we can discuss any additional problems that come up.

We ask that you leave your bike with us for upgrade work.  Repairs that take less time can be done by appointment, weekends included.

Over time we have learned there are a number of improvements, or as we like to call them, post-production repairs, that must be done to the Excelsior Henderson Super X.  The factory closed too early to fully shake out the bike and once the rubber met the road in the real world, "issues" came up.  The bike's safety, reliability and expense were all challenged.  Jamie decided early on that he could serve the community best by putting together a one-time repair package that would get ahead of the known problems.  We call it the Super X Solution.

Our basic upgrade package has evolved over the years as we listened to owners experiences and observed the types of repairs coming through the shop.  It began with ten items but has expanded to 25 specific actions we perform to eliminate  the safety, reliability and expense issues.  We manufacture improved versions of some parts and install them in place of the original.  Examples would be the Ignition Switch Bracket, Steel Scavenge Pump Bushing, Oil Pick-Up Tube our Stainless Motor Isolator Nuts, and our Performance Air Filter Kit etc.

By now, many bikes have had some of the improvements done by the time they get to us.  The final cost will reflect deductions in the total if that is the case.  Please contact us if you have any questions.

Diagnostic Road Test
Blue Print Transmission
Re-bush gears, check gears for concentricity,.  True Shafts.  Re-
assemble with spiral retaining clips and install our shift kit.  Use
longer bolts to install cassette so new thread is grabbed for better
Install Oil Pick Up Tube
Rebuild Clutch Slave Cylinder With Viton O Rings.  Flush Hydraulic Fluid
Inspect Shift Bracket, Replace with Reinforced Unit if Needed
Modify Battery Box to Reduce Pressure On Battery Cables
Reroute Crankcase Vent
Inspect Wiring Harness For Faults
Reroute some wiring and install additional shielding
Install additional ground strap
Install High Performance Air Cleaner Assembly With 2" or 3" K & N Filter
Inspect Front and Rear Brakes and Caliper Mounts
Clean corrosion from Brake Switches
Lubricate Throttle and Idle Cables
Install additional shielding on cables
Install Fan Assisted Oil Cooler
Install Teflon Scavenge Pump Bushing
Check Front Wheel Bearings and Torque Axle
Service Rear Wheel Hub
Bore and sleeve rear wheel hub with stainless steel.  Double row
bearings on right (drive)side.
Replace brake rotor and driven sprocket bolts with stainless, 6 pt
flange bolts for ease of future service.
Check Lights and Handlebar Controls
Perform the Following Adjustments as Needed
Shift Linkage
Belt Tension
Rear Shock
Steering Head Bearings
Throttle Control
Fastener Torque
Replace Ignition Switch Bracket With Heavy Duty Unit
Check Wheels
Check all Spokes, tighten as needed
Check Tires and tire pressure
Change Oil and Filter
Install Amsoil 20/50 V Twin Synthetic
Powder Coat Output Pulley and Exhaust Crossover Shield
Install Improved Stainless Steel Motor Mount Isolator Nuts
Test Fuel Pressure 
Inspect fuel line, replace as needed
Test ECU Function and All Sensor Operation
Tune with SuperXtune
Final Road Test

Call for estimate

Work ideally takes 4-6 weeks, but this greatly depends on our shop load.  We prefer to keep delivery open-ended, which allows us time to respond to emergencies or extended repairs we were not expecting.  Please make sure we are aware of any time constraints when you schedule your bike for work and we will make every effort to meet them.

Recommended Post-Production Repairs

Stage l
Additional Services 

The following items can be added to the basic package at the discounted prices shown.  Because we are already working on the bike, labor charges are reduced.

Install Power Point                                                                            45.00
Reinforce Kickstand                                                                        250.00
Modify  Stock Mufflers                                                                      42.50

Compression Test On Motor                                                           100.00                                                   
Replace Front Motor Mount Isolators                                           125.00
Replace Rear Motor Mount Isolators                                            300.00
Replace Front or Rear Brake Pads                                                140.00
Sleeve Front Wheel Hub, Change Hardware to Stainless           205.00 
​Upgrade to Tapered Steering Head Bearing                                 475.00

Super X Performance Solution
Stage II and lll

Heat is the major cause of engine failure in the Excelsior Henderson.  The lean tuning put in the ECM (Electronic Control Module) caused the cylinder heads to overheat and eventually cook the exhaust valves.  Even worse, to crack the cylinder heads in the area between the exhaust valves.  
 This is a fairly typical example.  You can                                                                   barely make out the crack between the                                                                   exhaust valves, but you can definitely see                                                               the burnt exhaust valve on the left.

We developed a shortage of front cylinder heads because of this and had to begin repairing them instead of replacing them.    We also wanted to come up with a good formula for porting and improving the cylinder heads overall.  To that end, Jamie went to his old friend from his days with Porsche, Larry Ladd .  Larry is an East Coast fixture in the world of competitive racing.  He works on cylinder heads used on everything from  funny cars to racing airplanes.  He developed a program for us to use that protects and preserves the heads as well as drawing out more horsepower.  The graphs below show the improvement to be had.      
Porting the heads improves air flow.  Testing shows  an 8 plus HP improvement can be gained by porting the heads
Also, excessive material that ends up being nothing but a heat sink is removed.  

The valve guides are lined with a special alloy that will retard wear and keep the valve travel true.
Stronger springs are used.
The pictures below show a ported and polished cylinder head's interior.
      Intake Port Reshaped                                Exhaust Port Reshaped
Freshly Cut Valve Seats
Stage II upgrades start with  the top end.  The cylinder heads are removed and  ported and polished.  Suspect valves are replaced.  If you wish, all valves can be changed to our custom made stainless steel or titanium versions.  The intake manifold is also modified.  We found the original design had unequal amounts of air going to each head so now modify the intake runners so that air and fuel flows 
at the same rate.  It is incremental changes like this that, when the work is completed, add performance, reliability and longevity to your motor.

In Stage III the entire motor is removed and disassembled.  Everything is carefully cleaned and inspected.  The cylinders, cases, rods and crankshaft are sent off to the machinist.  

The cylinders are fitment bored and honed.  A set of our custom Ross Racing pistons are hand fit to each cylinder.  Because the cases are a little too soft they  get steel inserts put in the head bolt holes to stop the problem with pulled threads.  New main bearings are installed, line bored and pinned.  The pistons, rods, and rings are sent with the crankshaft to the House of Balance where the crank is balanced.  The pistons and other parts are weighed so that the reciprocating weight can be used in the formula used for balancing. 

Once everything is ready it comes back to us and is cleaned again and ready for assembly.

Everything is then reassembled using new gaskets, o'rings, seals, etc. 

We also replace the head bolts with studs that are custom made for us by ARP.  We find this is a much better 
system for holding everything together.  If the motor needs to come apart again it will be much easier.  No more frozen head bolts.  We also use special Cometic head and base gaskets made to our specifications.  The head gaskets are a three piece design that remains sealed despite the normal growth and movement between mated surfaces.  The base gaskets are a true front and rear--yes they are different.  Both are viton coated and made from the best materials the manufacturer offered.  

Once everything is put back together, we tune the bike with SuperXtune.