Help and Advice from Jim from Old Website
Converting your black engine RL250 back to RL325? I bought one recently that I was told had been converted and the compression seemed extremely high. All black engines were made as the 322cc and some had a liner put in them to sleeve them down to 246cc as the 325 was a bit vicious. When converted to the 246cc they also skimmed the head and changed the pilot jet in the carb from 20 to 27.5. I assumed I had a head that had been skimmed but when I compared it with a friend's 325 the heads measured the same. It turns out that both bikes have the 250 head resulting in a compression ratio of 9:1 instead of the correct 7.5:1. Thanks to Steve Driscoll who sent me these photos of both heads, you can see the difference and where the head from the 250 has been skimmed and the combustion chamber milled out. I am having some conversion head gaskets laser cut to compensate for this so you can run a 250 head on a 325 bringing it down to the correct compression.
New Reed Petals = Better Bottom-End Performance
Would you like to improve the bottom end performance of your black engine Beamish and protect your engine from potential damage? Of course you would! It's very simple, change your reed petals for Hi-Tech fibre. The Beamish manual suggests you change your reed petals every 6 months or so, I would bet that your bike is still on the reeds it left the factory with - most are! If you take off one of your reed petals and hold it between your finger and thumb then bend it the way it has been operating all these years then bend it the other way, you will find that it is much stronger bending it the opposite way to the way it's been working. This is metal fatigue. At some point your reed petal could break off and be sucked into your engine. The good thing about the fibre reeds (apart from them working much better than your old ones) is that should they break up they won't do any damage as they are much softer than any other part they will come into contact with. I always fit new fibre reeds to any Beamish I rebuild or sell.
Finding the Right Yellow
There is yellow, yellow and yellow - but which one is Beamish yellow?! Other than the Heron Suzuki red/black Beamish you had the choice of yellow or buy another make of trials bike!
I was speaking to a friend who used to work in the factory. He told me that none of the yellows matched each other exactly anyway (tank, mudguards and side panels) so don't beat yourself up if you don't have an exact match!
3 March 2006: Update from Jim: I spoke to 'the' Graham Beamish and he told me that the colour is Suzuki and the same as used on the RM bikes in the late 70's and 80's - so there you have the answer from the horses mouth so to speak!
The closest colour code to Suzuki RM yellow is RAL1003.
How do I split my forks to replace the seals?
Answer: This is a very common one! You need to have the fork leg off, the top nut and spring removed. Try jamming a piece of dowel down the stantion to hold the top nut as you turn the allen key in the bottom of the fork leg.
Or, hold the station in a vice (protecting the chrome) and get a mate to pull the fork bottom to put pressure on the bolt. Use an air ratchet or an electric drill (on reverse) on the allen bolt to shock it undone.
Once you have one leg undone, make yourself a tool from a 13mm socketusing a Dremel for use on the other leg. Wrecking a socket for this purpose will save you a lot of trouble with the other leg!
How can I tell if my Black Engine Beamish is a 250 or 325?
Answer: The 325 barrel was black with '325cc' cast into the left side of the barrel. The 250 was silver and the '325cc' casting ground off. Better to go by the casting than the colour. Worst case, take off the head, the bore of the 250 is 70mm where as the 325 is 80mm.
What petrol mixture?
The original handbook (which came with the bike when I purchased it) clearly states that the petrol/oil mixture should be 20:1 ie 50ml of oil per litre. The bike smokes heavily and I've been advised by several trials riders that I should be running on 50:1 ie 20ml of oil per litre particularly as oils have improved over the years. What mixture do you use?'
Answer: If you use a good quality fully synthetic oil you can run your bike at 40:1 for road use and as lean as 50:1 for trialing. If you are not confident about such a lean mix, run at 40:1, a de-coke being cheaper than an engine rebuild! Modern day 2 stroke trials bikes run on 70:1.