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dadof2

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About dadof2

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  1. Unfortunately this was bound to happen. The issue of ever steeper, more dangerous sections to challenge improved bike and rider ability has been debated for many many years. I can remember Sammy Miller advocating a reduction of rear tyre size from 4.00 to 3.50 and that was before the michelin radial era. Bou will almost certainly recover physically, but whether he recovers mentally and regains his confidence 100% is questionable. It seems unlikely that organisers will want to reduce the spectacle of x trials. Therefore the compulsory wearing padded suits needs to be considered but even these are ineffective in preventing knee injuries such as those suffered by Michael Brown.
  2. Should I drain the carb

    What you say is correct but unfortunately the bit of fuel left in is the bit where dirt and water also tends to be. On some carbs this centre bolt also fixes the float bowl and loosening it can let dirt in at the float bowl joint. The 1970s Yams I owned had had proper drain screws and my 1970s and 1980s Suzuki and Honda have them. Carb manufacturers no longer including a proper drain screw is a right PITA.
  3. Should I drain the carb

    Someone said draining the carb is an easy job, just unscrew one bolt. The unfortunate fact is most if not all modern trials bikes do not have a carb drain bolt. This omission almost certainly cost me a Scott finish and in 2014 I think probably cost Dougie a win. Running the bike until the engine stops may not remove all the fuel from the float bowl but it removes a very significant amount. If you leave the bowl full the petrol creeps up the jets and evaporates leaving all the deposits exactly where you don't want them, ie in the jets. Also if there is less fuel in the bowl to evaporate it leaves far fewer deposits when it does evaporate and they re in the bottom of the bowl. This method also ensures the float valve is left open and the ealing face unstressed. Sometimes minute bits of dirt do get through the filter, bits or filter glue break off or dirt gets in the airbox / inlet hose during re assembly. Carb slow speed circuits can generally be one of two designs, and one is more sensitive to contaminated air than the other.
  4. Swingarm Theory

    I suspect something has been lost in translation and maybe a mix up between stability and traction. On any surface the closer the driving wheel is to the centre of gravity (shorter swing arm) the more traction there will be in the direction of travel. However in the same situation a long swinging arm / wheelbase gives more stability laterally, this is probably what is meant in the video. Perhaps the clearest example is in F!. The long wheelbase Merc is stable and dominant on faster tracks / high speed corners like silverstone because it has more lateral stability. The shorter Ferrari tends to be better on tracks that need low speed speed traction and more responsive cornering like Monaco. On these tracks the Merc has less traction and its rear tires tend to slip and degrade faster than the Ferrari. Edit - quote from Honda "A shorter wheelbase is better, especially if the traction is poor. The shorter wheelbase transfers more weight to the rear to help the bike hook up better and wheelie easier" Hook up is american for finding grip / drive / traction.
  5. Swingarm Theory

    Typical rear wheel adjustment is about 16mm with standard snail cams. Wheelbase is usually around 1295mm so 16 mm is about 1.2%. Although this is small 1.2% is sufficient to make a change to rear wheel grip and front wheel propensity to lift. If you generally ride slippy sections shorten the wheelbase, if you ride steep grippy stuff lengthen it. I have never noticed the difference between rear wheels positions on a trials bike but could feel it on an MX
  6. Running issue

    I agree with most of what has been written but I feel overweight / sinking floats are unlikely to be the cause of the symptoms you describe. Overweight floats cause rich running, your problem sounds like fuel shortage. is there a clogged filter in your fuel line, inlet to the carb or in tank / tank tap.
  7. Should I drain the carb

    One of my bikes had not been started since June until 2 days ago, and I can't even remember when I had the carb off - 2013 I think. It started 3rd leisurely kick. Fuel BP ultimate with optima fully synthetic racing oil at 30:1. I always make sure there is no water in my petrol tank either from condensation or fuelling in rain. I empty the carb after each ride by turning the fuel off and running then engine until it cuts out due to fuel shortage.
  8. Teresa May, Jeremy Hunt and several cabinet colleagues were watching Emmerdale on TV, believing that studying people in a Yorkshire village would enable them to connect with voters better and win the next election. Their hopes were dashed on Monday night when Jimmy King got a home visit from a GP. They then realised Emmerdale was actually fiction and not a real village.
  9. Where are all the entries????

    Baldilocks - You are right unfortunately. Nigel wrote "and your point is". My point is that trials with roadwork effectively exclude quite a number of riders, that would not have been the case in past times. Underlying factors in this are that modern bikes are too specialized, insurance costs and the number of steps and cost to get a full motorcycle licence. Look at the Westmoreland Club Lonsdale cup results (the excellent trial to which Baldilocks refers). Note the age profile of the clubman riders. The age profile of the green and hard courses is not published. The ages are a bit younger than the clubman but there are very few who are under 25 and virtually none in their teens. The ACU and the whole motorcycle industry seem oblivious to the damage the licensing laws are doing to trials entries and the uptake of motorcycling in general. The British conservative government (under whose watch these changes were introduced) saw no merit in these changes but went along with them because Tony Blair (previous labour government) had already signed up to EU harmonisation.
  10. Top End Carnage

    Judging by the carbon on the piston where a bit is missing, it looks as if it has been missing for some time. This would expose the top ring to excess heat and it would flex up and down, eventually fatigue cracking and breaking off. You need to find out if the big end is failing. As the engine is now 14 years old the big end should probably be replaced along with the mains and seals. I have known several instances of big end bearing cage parts causing this type of damage, even though the big end rollers and bearing surfaces were still OK.
  11. Where are all the entries????

    And to get back on topic. Recently there was what could be expected to be a very good trial that I have ridden in many times, had good results in and always enjoyed. For the last few years I have not attended. Another trial (not as good) about 10 miles away I and about 10 other locals attend. The difference between the two event? Roadwork. The better trial has roadwork. Some (about 75 to 80%) don't attend because their bikes are not legal or they don't have licences. The rest of us fully legal riders (the minority) don't go because the majority or all of our colleagues don't go. Edit follows The younger riders several of whom have 300s don't want to take the time and trouble of doing their tests to get on the road, nor do they want the subsequence expenses of VED and insurance just to do a very few road trials a year, the great majority of the events now being all off road multi lap. Even some of the older riders who have licences no longer bother having their bikes road legal - just don't think its worth it for a few road trials a year.
  12. Montesa 348 vs Bultaco

    Having owned several of both 348 Monts and 325 Bultos over a 10 year period I would say they are both excellent bikes. The 348 had a weak headstock and could have gearbox problems. I would quite happily ride either in modern easy, clubman and some hard route sections. No good for stop allowed sections or clutching. The middle steps at Newbiggin on the Alan trophy trial are now not used because "they are too hard for most riders on modern bikes". In the 1970s The whole entry used to tackle these sections on these old twinshocks.
  13. Where are all the entries????

    if you feel agrieved or insulted then perhaps you should look more objectively at your postings, or in simple terms get out more? My feeling are irrelevant - its the impression the tone of your posts gives to casual readers of the forum that could put them off. I rode yesterday at a practice ground, and at a very smal venue there must have been close to 80 local riders , competing Are you now implying because you attended an even of 80 riders trials is not generally in decline? If you think a 4rt is too expensive then you need to look at a) the way they hold there value, and b an older model which are reasnobly priced. Read what I said properly. I did not say that a 4rt was too expensive. In fact running a 4rt would cost a lot less than one of the other sports I participate in. no one has said there is one reason trials are reducing in numbers, just your thoughts are way off what others are seeing and experiencing. What you see and hear may well differ from what I do, did I say someone has given a single reason? Take a closer intrest in other sports they may suit you better? Are you implying someone should only be interested in one sport and do you really think I need your guidance on this?
  14. Trials gloves

    https://www.justgloves.co.uk/Work-Gloves/Assembly-Line-Gloves/Skytec-Basalt-R-Gloves Although not intended for trialling these gloves are very comfortable and give a good grip on the bars. Hardwearing also. This is not a "for sale" post. I have no connection with the link at all. I just happened to come across the gloves at a company that supplies and maintains equipment at roadworks / quarries etc.
  15. Fuel mixture Montesa 349?

    I would not go as far as looking for mineral oil but I would stick to original mix ratios which would be 25:1 or 32:1 A good oil at a good price for air cooled engines is oregon 2t chain saw oil. Modern fully synthetics intended for liquid cooled engines are low viscosity and rey on a high strength thin film of oil which is not ideally suited to the larger piston to bore clearances in air cooled engines which suit a more viscous oil. I think both Millers and Silkolene make classic air cooled 2T oils.
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