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By Wheaters
#99172
Good luck on the Exeter (the cold one). I have never attended that one, mainly due to me being up north and having to start work after the Christmas and New Year break. However, I’ve just retired so things may change. I do hope to get to the Land End to do my usual observing thing, even though it’s an 800 mile round trip and costs me a night in a hotel. The Edinburgh is more my local venue.
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By stinkwheel
#99192
rattonshaw wrote:
Sat Dec 04, 2021 8:42 am

The Durham area trials sections look definitely trickier than the MCC sections. The marking is different too. Put a foot down anywhere on an MCC section and that’s a fail; game over :( .
It was a proper "classic trial" scored like the MCC LDTs. So yes, each section 12 points. Some a countdown, some split 0, 6, and 12 and a couple all or nothing. Dab a foot (or stall, crash and fall over in the water, it's all the same) and the section is over (other than getting back off it again).

I think the 2014 EFI forks are more like a conventional Japanese damper rod fork. The tops aren't threaded into the casquette, just a push fit. I supect you'd get most of the oil out via the bottom bolt (with the caveat that the damper rod might decide to spin instead of it tightening/loosening). To get the springs out, you'd need to remove the fork from the bike and undo the top cap. They also have a spacer tube on top of the spring so you can mess with preload a bit by fitting different size spacers. It's one-up on the old ones, you need to pull the lowers and dismantle the damper rod on those to get at the springs. The earlier EFI ones are even more of a nighmare because the fork top-cap also screws into the casquestte so you have to turn the fork leg itself to unscrew them.
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By rattonshaw
#99197
Wheaters, retirement is great.
stinkwheel wrote: It was a proper "classic trial" scored like the MCC LDTs. So yes, each section 12 points. Some a countdown, some split 0, 6, and 12 and a couple all or nothing. Dab a foot (or stall, crash and fall over in the water, it's all the same) and the section is over (other than getting back off it again).
The MCC trials don't use points at all. For example, you could get as far as the Section Ends board with your front tyre over the line, but not your front axle, then come to a stop; that's a fail. Similarly, have a dab anywhere in the section, that's a fail. The results sheets will record 'S' (stopped), 'F' (footed), plus a few other remarks for the restart sections, e.g. 'DNS' (did not stop), 'RB' (rolled back). Obviously, the motorcyclists can put their feet down in the restart area of the section.

Good news on the front forks; not as bad as I thought. Still not sure how the top of the stanchion is clamped in the top yoke unless there is a taper (like the old Triumphs) or a pinch bolt in the top yoke.
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By stinkwheel
#99199
Ah, right, I thought they had 12 points in a section, I was sure I'd seen numbers on some of them when I watched videos. Not sure I'd do very well in that case because I think I only cleaned 2 sections at Durham :). Do they have a "special stage" where you ride your trials bike like an enduro bike against the clock?

I've not seen those forks exactly (I have the threaded-top version fitted to my 612 road bike) but I think they are held in by a combination of wishful thinking, light galling of the alloy and the top bolt pulling them up into the casquette. There MIGHT be a taper but I'm not convinced the monkey-metal the casquette is made of would cope with one without splitting.
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By rattonshaw
#99201
The 'special stages' are termed Observed Tests. And yes, you ride your bike like you stole it with the additional task of not dabbing because that'd be a fail. The times recorded are used to determine the Class winner out of those that have managed to achieve cleans in all sections. There are two Observed Tests in each trial and the two times are added together to come up with your total time. So you could record a slow in one test, but a fast enough time in the other to gain the class winner. Good fun doing the tests in the dark :lol:

When and if it comes to dismantling the forks, I'll take plenty of photos as a reference for anyone who tackles the task for this model year. All the documentation that I've managed to find is very sparse on the details and, according to some contains errors where documentation has not been updated.
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By Adrian
#99204
I know of at least four different types of fork in the UK Euro 3 EFI range! There are some drum-brake variants of the later forks too, fitted to Indian home market models, but forget those for now.

1. Electra-EFI, same forks as the Electra-X, they have the threaded stanchions which screw into the casquette and are the last of the old-style forks with the Redditch type damping.

2. Early C5 forks 2009 - 2011, still with threaded stanchion tops and leading axle, but with the later internals and no drain plugs. Screw-in plug on top of the fork stanchion has a left-hand thread.

3. B5 forks, plain stanchion tops held in the casquette by the large-headed allen screws with the 10mm thread into the crew-in plug, still with the leading axle, later internals and no drain screw. Note the screw-in plug for these has a right-hand thread

4. Later C5 and B5 forks, similar to 3 but without the leading leading axle.

Apparently for oil changes you have to remove the fork legs completely , unscrew the top plugs and tip the things upside-down to lose the old fork oil, which is utter pants for a mere oil change. IF YOU'RE CAREFUL you can drill and tap the bottom of the sliders for a 2BA or M5 drain screw with a fibre washer and also modify the top plugs so that they don't have to be removed for oil changes, allowing you to leave the forks in place for draining and refilling. I can post pictues if that will help.

A.
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By rattonshaw
#99209
Thanks Adrian. That's the most informative description I've seen on the EFI forks. It does makes you question why there are so many variations in fork design. I can understand the thinking behind supplying the in-line axle or the leading axle because these sliders give RE a means to obtain the appropriate steering geometry. What I can't understand is the reasons for the variations in the internal damping assemblies.

Are the Electra-X forks (Redditch type) just a single-way damped? Are the later internals two-way-damped? Looking at the parts catalogue, the later internals also have a rebound spring. Would the later internals fit the Redditch-type forks? There would be an advantage in having the later internals for an off-road bike? The rebound spring would reduce or stop the clunk when the forks top-out when the front wheel leaves the ground.

I'll look at the parts catalogue in some detail to make some comparisons.
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By stinkwheel
#99210
The electra X models, and in fact the Indian pre-unit bullets ones do have 2-way damper rods. Some of the later ones have an extra short spring on the bottom of the damper rod but I think it's more to increase the level of compression damping by applying pressure to the washer that covers the damper rod ports. I've tried with and without the spring and it seemed to make little noticeable difference to how they worked.

What I would say is I initially fitted the Electra X lowers to my 612 special (which is a 2003 pre-unit bullet) to allow me to use a disc brake, the ones that take a mudguard that bolts directly to the fork instead of having stays. I broke three lowers at the pinch bolt before giving up on those and fitting a set of forks from an early C5 with the threaded top cap. These fitted right into the yoke and casquette and have a much more robust lower.

The later forks (for the bullet EFI and Classic EFI) are noticeably smoother in operation than the pre-unit bullet/Electra X ones. The internals are totally different. I'd be surprised if they are interchangeable. If I read what you're asking correctly, you are wondering if you could fit electra x internals to a Bullet EFI fork. I'm pretty sure the answer is "No, and even if you could, you wouldn't want to.".

As to why so many different ones. I think one answer is they wanted to go for a more modern look with the Electra X (and the sixty 5) by having a plastic mudguard that bolts to the fork legs, this design precludes the use of shrouded forks. It was also their first attempt at fitting a disc brake so they had to re-design the lowers with calliper lugs. Reading between the lines, the pinch bolt area turned out to be pretty weak (try and find a right hand fork lower for these) and people preferred the more traditional design with mudguard stays and fork shrouds. There is a whole lot more metal and gusseting round the lower part of the fork on the Bullet EFI and Classic EFI ones.

As to threaded vs non-threaded fork tops. I suspect they had a huge stock of casquettes with threaded tops and kept using them up until they ran out, then moved to unthreaded ones. Why move from leading axle to straight? Again, I suspect it neccessitated a slight re-design in frame geometry to keep the correct rake-angle. In theory the leading axle would be a good thing for a trials bike giving a tad more force to the steering input and if you have a leading axle, it would be a good idea to stick with it.

Long story short, I'd stick with the forks and internals you have.
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By Adrian
#99213
The very first RE (India) disc brake forks were marketed as an accessory in the early 90's, they had a lug on each slider for a centrally mounted mudguard but further down than on the Electra-X/Electra EFI forks. My '61 Redditch Bullet had somehow acquired a set of these, along with a really bad drum brake conversion, but that's another story.

Early C5 forks will, as you and others have found out, fit the classic pre-unit casquettes as well as the alloy top yokes , allowing for traditionally mounted from mudguards and a disc brake in a solid set of fork sliders. I know our hosts sell conversion kits for the old drum brake forks, but I have been warned off those.

Early post-war Redditch telescopic forks were also plain-top until (I think) the 1954 season when the casquette headlamp was introduced. This type of fork was last used in the Fury and VAX interceptor (nothing to do with Covid 19). This type of fork actually breathed through holes on the underside of the top yoke via the fittings that screwed into the stanchion tops, all clever stuff. This sort of begs the question, if someone wanted to commit the utter sacrilege of fitting a B5 disc front end to a non-casquette Redditch Bullet or twin, could they do so? There actually are different ways of doing it, but that too is a topic for another post.

A.
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By Wheaters
#99217
stinkwheel wrote:
Sun Dec 05, 2021 8:42 am
Ah, right, I thought they had 12 points in a section, I was sure I'd seen numbers on some of them when I watched videos.
The so called “production car” trials and other bike trials are scored like that. They’re more often carried out as single venue events. They need more setting out and sufficient observers are needed on each section to ensure that competitors are properly scored; the difference between an axle being over a line or not is often very small.

On the MCC trials, the sections are usually much longer and use green lanes etc; observers often have to travel quite long distances between sections and rapidly set up another, “leapfrogging” the competitors.

A start line, a section ends line and restart box markers where needed are much less labour intensive than all the numbered posts needed to score the production car type trial and usually just three or four strategically placed observers can score the section.

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