So why do you have problem after problem with your Shovelhead, or know a guy who has? Sad to say it is virtually guaranteed to be bodged. De-bodge a Shovel and it is as good a runner as any Evo. Honestly! Why shouldn't it be? Only the head design is really different.

Let's take a look at the problem here ...

The trouble is that so many people, who honestly should know better, somehow seem to think that they can replace a £50 item with a £5 item and have the same result – with no problems. Or they can fix a £100 breakage with a £25 repair and not understand why they just wore out the £250 item next to it!

Bloody vandals! Bodgers! And all to save less money than they will spend on swill down at the pub while showing off how neat their new paint-job is!

Well son, you now have that fool's old bike. De-bodge it and it will do you proud for longer than you need worry about. Remember the cheapest repair you can make is the one you make only once, regardless of cost – and it's never really THAT much anyway. The dearest repair is the one you end up doing twice or leave until it's really knackered and has taken out something else with it.

Bear with me. Here we will start to look at the the whole thing ...

The first thing to accept is that we are dealing with a bike that is from fifteen to thirty years old and it would be a miracle if, as stated above, at least one owner in it's past hadn't been a clown. There are many things to check into so we will sectionalise the beast and go through as many as we can.

General.
When having a motor stripped down, clean all castings thoroughly and ensure that all oilways are clear of dirt and debris. When reassembling the motor ensure that all bushes and bearings are well-coated in oil to lubricate the part until the oil pump starts to supply oil to it again. This is critical.

Ignition settings and tolerances can all be found in the factory workshop manual – do NOT take on this job without a genuine factory manual. That kind of thinking is what made the engine the way it is!!

Top End.
Rockerbox gaskets don't normally leak on these engines so if you have an oil stain check the hold-down nuts/studs for a slack or stripped item. The plugs on the right-hand end of the rocker shafts are a sod for weeping. Remove them and clean the threads and add a good gasket-sealant to the threads. Check that the left-hand-end nut is tight and replace the O-ring (oem# 11101) that backs the right-hand plug when tightening it back on. If the rocker box is coming off then check that the end-float on the rocker shafts – which is listed at 3 to 15 thou. Make sure they are all within these numbers while edging closer to the 15 thou rather than the 3 thou so as to allow good oil flow. Also check the rocker end faces where they contact the valve tip for wear as if the hardened surface is worn through then the rocker arm wants replacing. While in this state take a look at the valves and guides. If there is any wear replace them as a valve/guide pair and only use good valves and guides that work well together.  Clean up the old guide before removing it (bead blasting works well) or you will rip out the head casting when you drift out the guide.

Have the seats re-cut properly before lapping in the new valves and you should need no repair/replacement there for 30-40,000 miles. Leave off the valve-guide oil seals if you want better lubrication rather than an anti-pollution medal. If your exhaust stud thread is getting tired then replace the unit with a fixed stud that uses a nut to retain the exhaust. This stops repeated wear on the stud hole threads and means your pipes won't keep coming loose.

One very important thing to check while your heads are off is the steel inserts that the cylinder head bolts screw into. Check the head-gasket face they sit in and ensure that they have not pulled proud of it. If they have then you MUST have that surface skimmed or you will constantly be suffering blown head gaskets.

Should you find, when riding your bike, that it blows smoke out of one of the exhausts in a big way then remove the exhaust pipe and shine a torch up into that port. If there is a lot of oil coming from the actual combustion chamber (past the exhaust valve seat) then remove the lowest head bolt. i.e. the rearmost on the back head and the foremost on the front head. If the bolt is smothered with oil then all that is wrong is your head gasket has blown where the rocker oil return hole is situated and is pumping oil into the cylinder. Remove the head (checking the inserts haven't pulled as already mentioned) and replace the gasket.

The rocker oil feed is via the small diameter. tube from the cases to the rear rocker box and from the rear rocker box to the front rocker box above the carburettor. They are often squashed – check 'em. The fittings that screw into the castings are restricted on late models (the 80 inch engines) as these had problems with over-oiling the top-end. Check that your engine has the correct fittings for it's year. If custom lines have been fitted the chances are that they are not of the restricted size and you may be suffering excess oil usage.

The earlier O-ring which sealed the intake manifold to the heads were a pain to fit but were a much better item than the later sleeve seals. If your heads are machined to use the earlier O-ring go with them. If you are using the sleeve type then ensure that your carb is supported solidly by a mount to the rocker boxes or the whole carb. assembly will move and the manifold will suck in air and screw up your carbonation – and eventually the seals too.

Using unleaded fuel in Shovelheads made before 1982-ish (there is a wide gray area here) will burn out your valve seats and do your valves no great favours either. When renewing your valve seats be sure to use the valves and seats which will work with unleaded fuel. These are okay for use with leaded fuel so you have the choice of either – at least while both are still available.

Pre 1977 1/2 model year bikes used a unique thread size for the tappet block hold-down screws. DO NOT mix these with later screws or use these earlier screws on later bikes as you will wreck the threads in the cases.

Cylinders.
There is not much to be said about cylinders except that when re-boring the pots ensure you have the bore done to the tight factory specs and with the correct crosshatching. And all done STRAIGHT!!! You would not believe some of the cylinders we get to see that have been bored here in this country.

Do not use circlip type piston-pin retainers in pistons which were designed for spiral type lock-rings or vice-versa. They are very likely to come out in use. Run-in the motor over at least 500 miles after boring to ensure good ring-seal. Torque down heads to an even 65 lbs/ft. Ensure that the crankcase face is flat where the cylinders fit to it. There must be no step or lip between the case halves or the cylinders will never seal on the base gasket. If you are replacing pistons that you have removed then ensure that when disassembling them you mark which one came from which cylinder and which was the front of each piston. Thus you can return them to the original cylinder in the original manner.

Cam Case.
Generator model owners should ensure that all pinion and gear bushings in their cam cover are without ANY wear. Replace without mercy. Check the camshaft lobes for wear, often found as minute pinpricks in the surface, this is the hardened surface breaking down. Replace cams found this way and give greater notice to all other bearing surfaces if you have found this warning sign. Take a look at the inner cam bearing in the case itself. This is a caged needle affair pressed in against a shoulder – usually it isn't all the way in to that shoulder which means that it cuts off the oil supply to itself. If replacing it (check camshaft where it sits in this bearing, if that face is worn then replace both cam and bearing) have it's 'named' end outwards and CAREFULLY press the bearing into the case until it sits against the shoulder – too hard and the bearing will push the shoulder out of the casting.

Camshaft end-float wants to be set at around 5 to 10 thou – shims are available to make this setting easy. Check out the lifter followers and lifter blocks for wear. 5 thou oversize lifters are available to suit reamed-out blocks if you need them. Always check your pushrod cover tubes to see if they have been swopped about – in 1977 the factory changed from a flat end to an embossed end to go with their move from cork seals to rubber O-rings. Make sure you have a set all the same and only use the correct seal to suit the tubes.

The stock hydraulics leave much to be desired and can be changed for a complete lifters/followers/blocks kit from such as VelvaTouch which work really dandy even with high-lift cams, or Jim's offering which uses the excellent Evo hydraulics. Or you can pull the hydraulics altogether and fit solid lifters with alloy pushrods. If you go this latter route – and I have used those for 20 years – then set them to only just turn when the engine is stone cold and the same valve on the other cylinder is as high as it will go. Check them again after a few hundred miles to allow for bedding-in – they should rustle but not rattle. While you are wandering around in the cam case area take a look at the breather gear. The later plastic one is better than the earlier steel one in that any debris that get into there will chew up the cheap plastic gear rather than your expensive alloy cases! If you are into real power mods then it is best to stay with the steel one as it is easier to modify and can stand the required changes. See if there are any grooves in the breather cavity. Really bad wear here may require a sleeve fitting. Do please set the breather end-float to factory specs. – again it is down to simple shimming. Earlier motors pre-73 had side-feed crankshafts instead of end-feed as on all up to today. Ensure that any replacement of pinion bushings – which should also be checked and tackled without mercy as it controls big-end oil supply – is done with the correct end-or-side-feed type to suit your crankshaft.

The oil pump requires a goodly amount of care in it's inspection. Faces should show no wear, nor should the pump shaft. Check the end play on the gears and renew the shaft seal – and fit it the right way round!! Re-seat the bypass ball valve. Do not go for any wise kits that promise extra oil pressure, said extra pressure will likely cause your crankshaft rollers to skate and damage your crankpin and, if all is working right, your top-end has too much pressure as it is! When fitting the unit back on make sure you tighten the bolts evenly and ACCURATELY, 65 inch/lbs is not very tight, but it is correct, so don't be tempted to over do it. If replacement of the pump is needed then don't waste money on a large capacity pump. The stock unit is more than sufficient as it is. Only late units are now available and need an accurate oil bleed-down hole drilled in earlier cases (all good shops will have a simple jig & be able to do the job) other than that it is a straight swop.

Crankshaft and cases.
Look for cracks in the inner case surface and have an expert repair any damage found. Frankly all other work here should be left to those with balancing jigs, truing jigs and years of experience! If you are replacing the big-end then replace the whole rod-set. It costs little extra and no H-D big-end goes without stressing the rods. Have the whole crankshaft balanced (the stock factory job was far from good). Don't fit S&S rods unless you re-balance – they weigh more than stock.

It is critical to set main bearing end float correctly – again replace it all as a shimmed set, no worries there. Fitting the bearing oil seal requires thought as to whether you have a pressurised or a non-pressurised primary case. Use a twin-lipped seal anyway.

I hope this is some use to you folk with the Shovelhead engine.