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tayld

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Everything posted by tayld
 
 
  1. I am very much with Woody regards enjoying trials while we can. Whatever type of bike we enjoy riding the sport needs youngsters on modern bikes. To give these younger riders and other new starters the desire to carry on the clubs who cater for them deserve to thrive. I rode twinshocks, with no great success in the sections, but really enjoyed the ride round. When the first monoshocks appeared they did not appeal. Observing today at club and centre level trials it is often the case a rider on a twinshock or pre-65 bike who can produce some really good rides on the same course as the modern bikes. Clubs do run easier trials for all-comers, our local club runs these on summer evenings. For those people who want a ride on their twinshocks and pre-65's why not try these easier club trials? If the sections are too hard ask for a five and enjoy the ride round and the crack with the other riders. Throughout the whole history of trials only a slack handful of people have actually made a living out of riding a trials bike so everyone else is presumably there to some degree for enjoyment. If the thought of riding a pre-65 or twinshock bike in an easy general club trial is daunting what about observing and using your old bike to reach your section? Some clubs still run trials with a good long lap and a bike is a good way of reaching a remote section. When a struggling new rider reaches your section give them encouragement, those riders wanting to carry on help preserve the sport. When the flags are pulled up at the end of the trial crank up your old bike for a gallop back to the start.
  2. Hi there, The Cycleserv TL250 manual details torque settings for all major engine and frame fasteners. Still readily available https://www.ebay.com/itm/HONDA-TL250-WORKSHOP-SERVICE-REPAIR-MANUAL-1975-/372906125272
  3. tayld

    Red/White Hondas?

    I have found these pictures taken at the 2012 Telford show. The bike is a "Short Stroke" 306 ridden by Marland Whaley from the USA. Photographic quality is unlikely to match Deryk's.
  4. tayld

    Red/White Hondas?

    On hearing mention of the "red/white" Hondas my first thoughts would be of the works twinshock bikes of the mid-1970's. If my memory is correct the first of the red/white works bikes appeared relatively soon after Sammy Miller's involvement. Initially there were chrome framed bikes with blue paintwork then the red and white bikes. I recall being at the Allan Jefferies trial when there were both chrome/blue and red/white bikes together. Both versions at the trial were the XL/TL based "long stroke" bikes. The works red/white "long stroke" 305 was promoted in the press of the day as a prototype for a production bike, sadly this never happened. Honda used the red/white colour scheme for its works trials bikes on both sides of the Atlantic and also for both "long stroke" 305 and "short stroke" 306 bikes. Subsequently an all red colour scheme was used for both "long stroke" and "short stroke" bikes. It would be great to see pictures of the red/white twinshocks as they were purpose built works bikes with little connection to a production bike. I am more than happy for any of the above to be corrected as it is the recollections from almost forty years ago.
  5. Hi there, I have had a look in my 1987 RTL250 manual. Front spokes are sold as a set of spoke and nipple. The part numbers in my book are 446A0-KR9-000 and 446B0-KR9-000, the latter number appears to be the brake drum side. I have entered both parts into Lings Honda's part number search and this shows both spoke sets still available within three days at about £5 per spoke with nipple. Hope this helps.
  6. Hi there, I once had a bike with an alloy tank secured with a circular section rubber band. When it failed I used the drive belt from a Hoover upright vacuum cleaner. They might not be available anymore but could be worth looking for.
  7. Hi there, The rubber front sprocket cover is held on three pegs. Two of the pegs are part of the steel chain guide which is a close fit around the front sprocket. If you send me a PM with an e-mail contact a picture can be forwarded.
  8. When checking the carburettor see if the float height is correct to the specification. There can be some different figures quoted but a careful check should find the right value for your carb. Another check worth doing would be look at the contact breaker points with the engine running. If there are a profusion of sparks the condenser might be on its way out. Hope this is of help.
  9. With the gearbox in neutral the dot on the selector drum gear should align with the line stamped into the selector quadrant. Check the selector pawls are undamaged. Damage to the pawls is quite common. The slot the pawls slide in is not symmetrical. Some fine tuning of the selector mechanism is possible by slackening the M6 nut shown to the right of the selector drum gear in your picture then rotating the eccentric to achieve the best selection. Tighten the M6 nut each time after adjusting the eccentric. Hope this helps.
  10. tayld

    248 Chain Tubes

    Hi there, You are right about the front end of the chain tubes being supported on the chain when it is fitted. There is only the "T" shaped bracket. The "T" shaped bracket can wear out where it pivots on the rear wheel spacer. If you have a chain tensioner fitted with the pad just behind the gearbox sprocket the front end of the chain tube should be clear of the pad. Replacement tubes we have bought lately fit both top and bottom runs of the chain, the bottom tube has to be shortened if a chain tensioner is used. Saw the excess off with a junior hacksaw.
  11. I would agree with the previous reply. Before fitting a new 28 mm OKO to a Montesa Honda MH349 we found the float height needed resetting before use. The float height setting for the similar Keihin PWK carburettor is 19 mm from the float bowl gasket face to the highest point of the float. Check the 19 mm dimension with the tang of the float resting on the float needle tip without compressing the spring inside the float needle. This 19 mm dimension also works well with the OKO flat slide. To make checking the dimension easier start by holding the carburettor so the float bowl joint face is vertical with the float pivot pin at the top and horizontal. The float tang should be clear of the float needle, tilt the carburettor so the float moves towards the float needle. Measure the float height when the float tang just touches the needle tip. If the float height is out the adjustment is made by carefully bending the float tang. Also check there is no water in the float bowl. Hope this helps.
  12. Hi there, Looking at the picture the bike looks very original. It appears to have the Akront fat bars and twistgrip which came with the bikes when they were new. The rear suspension units are also the same as fitted to my own 349 which was bought new in 1980. From memory they are Telesco Hydrabags. I cannot recall if my own bike came with a rear chain tensioner when new. I know there was one when I parted with the bike. The tensioner mounting boss is fitted to the end of one of the crankcase screws in place of the nut. From the picture I would suggest lowering the stanchions through the fork yokes until there is about 6 mm of the stanchion above the yoke. This should keep the steering quick enough without the front mudguard contacting the exhaust on full fork compression. The rear brake torque arm looks too long, standard should be about 220 mm between the centres of the holes. A new rear brake cable may be needed. Changing the torque arm should improve the action of the brake. If the kickstart lever is mounted too far forward the stop lug on the kickstart shaft can punch a hole through the flywheel housing. When the foot pedal is folded aim for it to be parallel to the cylinder fins or just pointing downwards. Gearing is good with a 10T gearbox sprocket and 40T on the rear wheel. Set the ignition timing at 3,0 mm BTDC for a good starting point, if the power is too fierce try retarding the ignition. The joint between the main exhaust and rear box is sealed with two "O" rings fitted in grooves in the rear box pipe. Hope the above helps.
  13. Hi there, We have made a set of notes for setting up the 349 gearchange. Send a PM for details. Best regards.
  14. tayld

    Montesa 349

    Hi there, The late model 349 and MH349 definitely run better with the heavy standard rear box. I have a virtually unused WES back box somewhere in the loft. The standard rear box has a baffled first chamber and an absorption second chamber. The first chamber can be heavily blocked with carbon and oily gunge. With care the standard rear box can be cleaned and repacked without having to reweld it.
  15. Hi there, Honda have provided a level plug to check the engine oil. With the engine cold sit the bike level on a paddock stand. Looking at the clutch case there should be a level screw tucked away below the bulge for the clutch just in front of the kickstart lever. Remove the oil filler cap from the front of the clutch case then remove the oil level plug. The oil level is correct when oil just begins to trickle out. The level plug is only M6 so the oil should run out slowly. If no oil runs out add new oil slowly through the filler hole until it runs out of the level plug hole. To avoid over filling let the oil run out until it stops. Check the sealing washer and refit the level plug screw, take care the thread in the case is easily stripped. Hope this helps.
  16. Hi there, As Woody noted are you certain the ignition including spark plug is working and correctly timed? A leaking crankshaft seal or blocked exhaust can also have an effect. When no known settings are available the tuning guide published by Amal is very useful. http://amalcarb.co.uk/downloadfiles/amal/Mk1_Hints_and_Tips.pdf The five step tuning sequence does work providing the engine is actually working against a steady load and you know where the slide is at each stage. If in doubt start with a large main jet and work down from there in stages. The main jet does need to be done first. When adjusting the pilot air screw (and pilot jet size, when fitted) make sure the slide is not set too high. Hope this helps.
  17. Hi there, Do you get the same seepage if the bike is stored overnight on a workshop stand which keeps the bike level? Unless the bike is leaning over at very steep angle on its stand to cause the leak it could be worth checking the float height. Check the manual for the correct float height and the method of checking it. Assuming "new float valve" means the float needle plus perhaps its seat checking the existing float (if it is of hollow construction) for leaks might be worth a try. Remove the float from the carb and immerse the float fully and quickly into hot water, watch for a small stream of air bubbles to indicate a leak.
  18. Hi there Gareth. The bearings are held apart by a shouldered spacer tube. After removing the circlip the bearings have to be drifted outwards from the opposite side of the hub. Removing the first bearing needs a drift which is a very good fit in the bore of the opposite bearing in order to locate the end of the thin shoulder of the spacer. The end of the spacer is easily damaged. To make the job easier use a heat gun to warm the bearing housings before removing and refitting the bearings. Before fitting the new bearings make sure the spacer tube is undamaged, check by seeing if the spacer slides easily on the spindle. Hope this is of help.
  19. Hi there Gareth, Your MH123 conical front hub's small spoke flange is made of steel and held on with three nuts. After removing the nuts there should be a plain flange followed by the spoke flange. Both flanges can be removed for painting. Hope this helps.
  20. If you are starting from scratch in setting your carburettor check the jets, needle and slide are correct for your bike. The original Montesa owners manuals have details of the original settings. A new correctly oiled air filter is an advantage if the existing filter is getting a bit crumbly. Start by adjusting the throttle stop screw by backing off the screw until the slide reaches the absolute bottom of its travel. Make sure there is a little slack in the throttle cable. Then lift the slide by 1.1/2 to 2 turns of the throttle stop screw. If the slide is too high the carburettor's pilot system will not work properly. Now gently screw the pilot screw in till it stops then wind it back out 1.1/2 turns to begin with. Start the engine and let it warm up fully. If it does not tickover screw the throttle stop screw gently in until a tickover is obtained. If it ticks over too fast wind the throttle stop screw out. We finally set the pilot air screw by listening to the engine revs, turn the pilot air screw slowly in both directions until maximum revs are attained. Turning the screw out weakens the mixture and inwards richens the mixture. Too weak or too rich a mixture will cause the revs to drop or the engine to stop. When the point of maximum revs has been found the throttle stop screw will probably need adjusting to your preferred tickover speed. Once set a half turn of the pilot air screw in either direction should cause the revs to fall. When the tickover is how you want it check the throttle cable for excess play. Hope the above is of use.
  21. Hi there, I have measured my MH349 with the bike on a stand so the front wheel is clear of the ground. This means the measurement is not affected by sag in the springs. The distance from the spindle centre to the bottom of the bottom yoke measures 57 cm. The top of stanchion (measured without the nut) is proud of the top yoke by 6 mm, this nicely quickens the steering. The stanchions used in the MH349 are longer than those used in early 349's. Hope this helps.
  22. tayld

    Montesa Colour

    We struggled to find a good match in the RAL/BS series for the red on our MH349. The MH bikes seem to have a more orange tint than the comparable Montesa badged bikes. What we have used as a near substitute is Ford Carnival Red. It is a popular colour so your local Halfords should have it available.
  23. Hi there, Was powder coating/painting the frame part of your project? If it was make sure the coil bracket is free of paint for a good earth between the coil and the frame, also make sure there is good electrical contact between at least one engine lug and the frame. A poor earth can cause mysterious faults. All the best.
  24. The 349 carburettor settings varied over the time it was in production. The number stamped on the side of the carb identifies the original specification. Montesa's original owners manuals have been available from Caroline Sandiford. These manuals also give details of the original settings. Watch out for wear in the carb body and a replacement carb fitted from another bike.
  25. Although it might not be the original gearing I would suggest 10T gearbox and 40T back wheel. This gives good all round gearing.
 
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