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.















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.  



​R & R Transmission:  Blueprint and Re-bush gears to shafts.  Assemble with Spiral Clips.  Replace shift detent wheel and tension spring with our improved parts to reduce the likelihood of false neutrals.

Rebuild Clutch Slave Cylinder replacing OEM O'rings with Viton material that is compatible with DOT 5 Brake Fluid.

Install Scavenge Pump Oil Pick-up Tube to eliminate cavitation and better control the oil level in the primary.

Inspect Shift Bracket and Repair if possible.

Reroute Crankcase Vent to the Rear Fender.

Check Condition of Wiring Harnesses, Install Additional Ground Strap.

Bore and Sleeve Rear Wheel Hub, Machine to Accept Three OEM Wheel Bearings 

Check Front and Rear Brakes, Replace Pads, Flush and Bleed as Necessary.

Check Intake For Air Leaks and Install New Seals and Gaskets as Necessary.

Clean and Balance Fuel Injectors if Needed.

Install High Performance Air Cleaner with 2" K & N Filter.

Install Golon (made in USA) 10micron External Fuel Filter w/New Line.

Lubricate and Adjust Throttle Cables.

Inspect Front Brake Caliper Fasteners and Torque. (R & R Front Wheel to Access Caliper Rod).

Check Front Axle Fasteners and Torque.

Replace OEM Ignition Switch Bracket with our two piece Stainless Steel Component that includes a Saddle to Secure the Bracket and Eliminate Vibration.

Install East Coast Fan Assisted Oil Cooler Assembly with Switch.

Install Steel Scavenge Pump Bushing.

Inspect Riser Bushings and Replace if Needed.

Inspect Lights and Handlebar Controls. Clean Front Brake Switch Contacts.

Powder Coat Output Pulley and Exhaust Crossover Shield.

Install Improved Stainless Steel Motor Mount Nuts and update Front Isolators to Improved Version. Replace Rear Isolators and Mounts. This is designed to pull the Frame Together, Eliminating the gap between the frame and mount preventing lateral movement of the engine and bowing of the frame.

Install Battery Tender Lead to the Starter Relay and Frame to eliminate loose Connections at the Battery Posts.

Optional but Recommended Work.

Replace Upper Steering Head Bearing with Tapered Bearing.  (Cures Problem with Wobbles).

Safety Wire Fasteners in the Lower Cam Cover.  (These 1/4-20 bolts located over the exhaust ports can loosen over time due to heating and cooling cycles and come all the way out causing mayhem.)