Hitchcocks Forum

Hi
New to Royal Enfields, having just bought a 1991 500 export bullet and have a query on the size of spanners to adjust the tappets. So far everything I have come across on the bike has been metric but not it appears the locknut and adjuster nuts on the end of the push rods. Can anyone advise please?

John

Ps Really enjoying the bike, what a hoot!

Hello there JOHN C and welcome indeed...If I may freely misquote Shakespeare}---"We few, we happy few, we band of brothers;
For he to-day that mends his Enfield with me
Shall be my brother; be he ne'er so vile", .................One thing about this forum you may have noticed is the tendency for owners to improvise or alter an existing situation......And here is one such case in point re}-- tappet adjustments..........The tappet cover plate fits over a stud that is screwed into the engine casing and has a nut on the outside which holds the plate in place....It's this stud that gets in the way of your spanners when trying to tighten etc. the adjusters and nuts..................... If you change that stud into a bolt which clamps the access plate in place then there is now plenty of room to use standard spanners instead of buying or making "special tools".......I've done it on both my Classic 500's and all is well............Remember to get the piston at TDC, Compression stroke to ensure that the valves are fully closed...

Unless there have been a large number of replacements I'd be surprised if there was much metric on a 91 Bullet. My mostly 92 350 is all Whitworth head sizes.

Was there a 500 in 1991? I thought they started in 93? But IKBA on Indian stuff! REgards, Mark

The "uncommon" size metric spanners will fit, 11,12 etc will fit some imperial size nuts&bolts

Hi Mark M. Mine is a 1992 500 Indian built Export model. I understood the 500s started production in 1991 but I could be corrected. To go back to the origin of this thread the nuts, bolts and fixings on mine can be anything from Whit, A/F to Metric. I agree with the above advice to remove the stud that holds on the tappet cover makes the job is much easier. Start with a cold engine with the piston at TDC on the compression stroke and adjust both push rods to zero clearance, best done by just being able to spin the push rods when they have as little resistance as possible with no perceptual up and down movement. This takes a bit of practice to get spot on but peservere until no tapet noise is heard when the engine is running and all will be well.

1/4 and 5/16 Whit.

There is a complete mixture of threads on these bikes. Metric, BSF, Whitworth, British Standard Cycle, and BA.
If you are not familiar with Imperial sizes, do not despair, you only need one set of Imperial spanners.
Each system may call the fastening a different size but the spanners are the same, it's the threads that are different(except BA but they are so small you can manage with pliers if you have to)
Imperial spanners can often be picked up at jumbles.
It's also a good idea to get a thread gauge and a chart of different thread per inch used on the different systems so you know which thread you are dealing with.
Using the wrong spanners, even if they "nearly fit" is a good way of rounding off nuts and bolts and adjustables are always a last resort.

Count Johnny has the correct answer to the original question 1/4" whitworth & 5/16" whitworth spanners!