Cylinder
FORGED PISTON (6.5:1)
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This is an English made forged piston which is a straight replacement for the standard piston. Made by Omega, it gives a very strong and robust piston without changing the standard compression ratio of approximately 6.5:1 It is supplied with rings, gudgeon pin and circlips. Available in STD, +20 and +40. Suitable for all 500 Bullets from 1953.
| PART No. | DESCRIPTION | PRICE | |
| 90204 | PISTON COMPLETE, STANDARD, FORGED, 84mm (Omega/Accralite) | £135.00 | |
| 90205 | PISTON COMPLETE, 84mm +20, FORGED (Omega/Accralite) | £135.00 | |
| 90206 | PISTON COMPLETE, 84mm +40, FORGED (Omega/Accralite) | £135.00 |
EUROPEAN MADE PISTON (500cc)
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This piston is fitted as standard to late 90's European 500 Bullets. It gives a compression ratio of approximately 6.5:1. It comes complete with rings, gudgeon pin and circlips. Available in Std, +20, +40, and +60.
Suitable for all 500cc Bullets from 1953.
| PART No. | DESCRIPTION | PRICE | |
| 38504A | PISTON C/W RINGS, APPROX 6.5:1 | £60.00 | |
| 38504A/20 | PISTON C/W RINGS, APPROX 6.5:1 | £60.00 | |
| 38504A/40 | PISTON C/W RINGS, APPROX 6.5:1 | £60.00 | |
| 38504A/60 | PISTON C/W RINGS, APPROX 6.5:1 | £60.00 |
FORGED PISTONS (500cc and 535cc)
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After years of experimenting, we now have available some excellent quality English made forged pistons. These were originally designed for our competition engines, but have now been refined to allow closer bore to piston clearance for road going Bullets. This piston gives a compression ratio of 8.5:1 so is ideally suited for every day use or for those of you who want that extra bit of performance coupled with a strong robust, reliable piston. These are available in 500cc standard and +20. Or why not bore your 500 barrel to 87mm and fit our 535cc piston? They come complete with rings, gudgeon pin and circlips.
Note: We would also suggest a higher grade of fuel is used when raising the compression of your engine.
| PART No. | DESCRIPTION | PRICE | |
| 90016 | PISTON FORGED, WITH RINGS, 500cc STD | £150.00 | |
| 90017 | PISTON FORGED, WITH RINGS, 500cc +20 | £150.00 | |
| 90020 | PISTON FORGED, WITH RINGS, 535cc STD | £150.00 | |
| 90021 | PISTON FORGED, WITH RINGS, 535cc +20 | £150.00 |
HIGH COMPRESSION PISTON (500cc)
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These pistons are American made, and give a compression ratio of approximately 9:1 with the head gasket fitted (9.5:1 without gasket). They come complete with rings, gudgeon pin and circlips. Available in: +30, +40, +50, and +60 only.
Suitable for all 500cc Bullets from 1953.
Note: If you are using the standard bottom end, we suggest you use a compression plate with this piston to lower the compression. We would also suggest a higher grade of fuel is used when raising the compression of your engine.
| PART No. | DESCRIPTION | PRICE | |
| 42877/40 | PISTON, 84mm +40, 9:1, C/W RINGS | £80.00 | |
| 42877/50 | PISTON, 84mm +50, 9:1 C/W RINGS | £80.00 | |
| 42877/60 | PISTON, 84mm +60, 9:1 C/W RINGS | £80.00 |
HIGHER COMPRESSION PISTON (350cc)
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This piston gives approximately 8:1 compression and comes complete with with rings, gudgeon pin and circlips. Available in Std, +10, +20, +30, +40, +60 and +80.
| PART No. | DESCRIPTION | PRICE | |
| 17459 | PISTON COMPLETE, STANDARD | £45.00 | |
| 17459/10 | PISTON COMPLETE +10 | £45.00 | |
| 17459/20 | PISTON COMPLETE +20 | £45.00 | |
| 17459/30 | PISTON COMPLETE +30 | £45.00 | |
| 17459/40 | PISTON COMPLETE +40 | £45.00 | |
| 17459/60 | PISTON COMPLETE +60 | £45.00 | |
| 17459/80 | PISTON COMPLETE +80 | £45.00 |
FORGED PISTON (350cc)
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An English made forged piston by Omega giving approximately 8:1 compression. Strong, light, robust and extra performance makes it an ideal replacement for the standard piston. Supplied complete with rings, gudgeon pin and circlips. Available in Std, +20, +40, +60 and + 80.
| PART No. | DESCRIPTION | PRICE | |
| 90260 | PISTON COMPLETE, STANDARD, FORGED, 70mm | £145.00 | |
| 90261 | PISTON COMPLETE, 70mm +20, FORGED | £145.00 | |
| 90262 | PISTON COMPLETE, 70mm +40, FORGED | £145.00 | |
| 90263 | PISTON COMPLETE, 70mm +60, FORGED | £145.00 | |
| 90264 | PISTON COMPLETE, 70mm +80, FORGED | £145.00 |
PISTON RINGS - 350cc
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These are the standard style rings. **EUROPEAN MADE**
| PART No. | DESCRIPTION | PRICE | |
| P/RING | PISTON RING SET, (for 1 piston) various 250-700cc models (European Made) STANDARD (70mm) | £16.00 | |
| P/RING/20 | PISTON RING SET, (for 1 piston) various 250-700cc models (European Made) +20 | £16.00 | |
| P/RING/40 | PISTON RING SET, (for 1 piston) various 250-700cc models (European Made) +40 | £16.00 | |
| P/RING/60 | PISTON RING SET, (for 1 piston) various 250-700cc models (European Made) +60 | £16.00 | |
| P/RING/80 | PISTON RING SET, (for 1 piston) various 250-700cc models (European Made) +80 | £16.00 |
PISTON RINGS - 500cc
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These are the standard style rings. **EUROPEAN MADE**
| PART No. | DESCRIPTION | PRICE | |
| P/RINGA | PISTON RING SET 500cc STD (European made) | £17.50 | |
| P/RINGA/20 | PISTON RING SET 500cc +20 (European made) | £17.50 | |
| P/RINGA/40 | PISTON RING SET 500cc +40 (European made) | £17.50 | |
| P/RINGA/60 | PISTON RING SET 500cc +60 (European made) | £17.50 |
350cc ALLOY CYLINDER BARREL
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For lightness and better heat dissipation. Please note that these cylinders have been through our own stringent 10 point check and rectified in various areas to ensure they are what we consider to be of an acceptable quality. This now includes a steel insert for the thread between the pushrods to replace the standard helicoil.
We also stock unchecked alloy cylinders which have tolerances outside our preferred standards. Whilst Hitchcock's do not use or endorse these, they do offer a cheaper alternative as a basis for improvement.
| PART No. | DESCRIPTION | PRICE | |
| 200060 | ALLOY BARREL 350cc | £125.00 | |
| 200060A | ALLOY BARREL 350cc (unchecked) | £80.00 |
500cc ALLOY CYLINDER BARREL
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For lightness and better heat dissipation. Please note that these cylinders have been through our own stringent 10 point check and rectified in various areas to ensure their quality. This now includes a steel insert for the thread between the pushrods to replace the standard helicoil.
We also stock unchecked alloy cylinders which have tolerances outside our preferred standards. Whilst Hitchcock's do not use or endorse these, they do offer a cheaper alternative as a basis for improvement.
| PART No. | DESCRIPTION | PRICE | |
| 200071 | ALLOY BARREL, 500cc | £150.00 | |
| 200071A | ALLOY BARREL, 500cc (unchecked) | £85.00 |
535cc ALLOY CYLINDER BARREL
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For lightness and better heat dissipation. Please note that these cylinders have been through our own stringent 10 point check and rectified in various areas to ensure they are what we consider to be of an acceptable quality. This now includes a steel insert for the thread between the pushrods to replace the standard helicoil.
We also stock unchecked alloy cylinders which have tolerances outside our preferred standards. Whilst Hitchcock's do not use or endorse these, they do offer a cheaper alternative as a basis for improvement.
| PART No. | DESCRIPTION | PRICE | |
| 200073 | ALLOY BARREL, 535cc | £150.00 | |
| 200073A | ALLOY BARREL, 535cc (unchecked) | £95.00 |
COMPRESSION PLATE (500cc ONLY)
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These are made out of alloy and are available in either 2mm or 3mm thickness. Can be used in conjuction with 42877 piston or any high compression piston to lower the compression.
| PART No. | DESCRIPTION | PRICE | |
| 200480 | COMPRESSION PLATE, (ALLOY) 2mm 500cc | £10.00 | |
| 200481 | COMPRESSION PLATE, (ALLOY) 3mm 500cc | £10.00 |
BIG BORE KIT
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Comprises of large bore cast iron or alloy barrel and completely redesigned piston to give a new engine size of 535cc with a choice of compressions. This is a direct replacement for the standard barrel, but will also compliment the tuned cylinder heads that we offer.
Note: that the alloy barrels used in our big bore kits are the ones that have been through our 10 point quality check.
| PART No. | DESCRIPTION | PRICE | |
| 200074A | BIG BORE KIT, (IRON BARREL) with forged 8.5:1 piston | £280.00 | |
| 200074C | BIG BORE KIT, (INDIAN made ALI BARREL)+FORGED 8.5:1 PISTON | £290.00 |
ELECTRA BIG BORE KIT AND FORGED PISTON
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Finally a big bore kit for the 500 Electra to take it out to 535cc. It has taken a couple of years to develop but we now have a design and piston that performs well. At a compression ratio of approximately 8.5:1 and the extra 35cc engine size it gives the extra performance you are looking for. With the benefits of a strong, robust and reliable forged piston, it is an excellent improvement. You can either bore your 500 barrel to 87mm and fit our 535cc piston or have a matched cylinder and piston -- They come complete with rings, gudgeon pin and circlips.
| PART No. | DESCRIPTION | PRICE | |
| 90137 | BIG BORE KIT, 535 ELECTRA | £315.00 | |
| 90135 | PISTON FORGED, WITH RINGS, 535cc STD ELECTRA | £150.00 |
EFI MODELS BIG BORE KIT AND FORGED PISTON
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This big bore kit includes a forged piston developed by Wössner pistons in Germany in conjunction with Fritz Egli and Jochen Sommer. It gives better performance and very good torque. It is supplied with a replacement cylinder head gasket and increases the engine size to 535cc with a compression ratio of approx 8.5:1.
| PART No. | DESCRIPTION | PRICE | |
| 90224 | PISTON, WITH RINGS, 535cc STD EFI models (With head gasket) | £140.00 | |
| 90225 | BIG BORE KIT (MATCHED CYLINDER & PISTON), 535 EFI | £375.00 |
CORDRINGS (350 AND 500cc)
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These English made piston rings are made up of several rings for each groove. They give better compression and oil control especially if you have a worn bore.
Note: The manufacturer has now discontinued the Bullet range of rings, so stocks are limited.
| PART No. | DESCRIPTION | PRICE | |
| 90074 | CORDRING, 350cc, +80 (72mm) REDUCED FROM £24.00 TO £15.00 TO CLEAR. | £15.00 | |
| 90067 | CORDRING, 500cc, +40 (85mm) - REDUCED FROM £24.00 TO £15.00 TO CLEAR. | £15.00 | |
| 90068 | CORDRING, 500cc, +60 (85.5mm) REDUCED FROM £24.00 TO £15.00 TO CLEAR. | £15.00 |
CYLINDER LINER
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A centrifugally spun European made cast iron liner suitable for use in the cast iron (NOT suitable for alloy) cylinder barrels.
| PART No. | DESCRIPTION | PRICE | |
| LINER | CYLINDER LINER 84mm | £55.00 |
PISTON CIRCLIPS
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Most Royal Enfields use a standard wire circlip. These are not the easiest to fit and remove. We have produced a batch of the correct specification wire circlips but with the tags as shown in the picture.
Please note: These are to be fitted to the standard pistons only, they are NOT suitable for our aftermarket forged pistons.
| PART No. | DESCRIPTION | PRICE | |
| 20363A | CIRCLIP, PISTON (with tags) **not for forged pistons** | £0.50 |
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