OzVMX Forum
Marque Remarks => Spaniards (Bultaco, Ossa, Montesa etc) => Topic started by: YUMASTEPSIDE on September 25, 2010, 06:18:52 pm
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A mate just picked up a pair of 250 enduro's, and we hope to have them at least rideable for Rockley :-\ :-\ :-\........so all you monty experts out there, how about some info ?? For starters, what are they called, does the enduro model have some sort of designation ??What are the things to look out for on these models, problems, etc. What should be done to them to make them reliable,etc, and any basic info like which plug works best, jetting, anything that can help, as we're complete mugs at this monty stuff ;D ;D ;D
Roger
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king scorpion?
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.........no, a proper enduro model........
(http://i727.photobucket.com/albums/ww272/yumastepside/100_6934.jpg)
........same model as this one
Roger
( sorry Firko, yes, another pair fron Ronny )
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That's much the same as mine, Roger. Except mine's got leading axle forks.
I'm certainly no expert, but I learned a lot about these things in the past few weeks, so let me know what they need.
I've got parts manuals and would recommend Jared at Southwest Montesa for parts.
P.S. Should be designated 54M
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I didn't think they had leading axle til well into the '80s.........my H6 didnt
(http://i727.photobucket.com/albums/ww272/yumastepside/IMGP5001.jpg)
Roger
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The most important thing I've learned about Montesa's is don't try and work out their models. :D
Here's mine.
(http://i467.photobucket.com/albums/rr37/Tony_T12/_MG_9264.jpg)
It came with a steel headlight on brackets which supposedly was replaced by the plastic unit by then. But it had one. ???
http://www.montesaweb.com/secciones/detalles.aspx?id=121 (http://www.montesaweb.com/secciones/detalles.aspx?id=121)
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Not 1974 models I'm afraid. They are '75/76 models. I had one exactly the same purchased in 1976. Great bike you can not kill them as they where based on the VR/V75 type of engine. I may have some parts let me know what you need and I'll have a look. I know I have a couple of NOS exhaust silencer internals. May also have a parts book. I'll have a look.
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It is an Enduro 250 or a 250A. Enduro 250's were built from 74' to 76'.
starting at 54M0001 (3,853 produced)
The 250A was built in 76 and begins with 54M66001. (280 produced)
This model came with either an Amal L 2932 or a Bing 54-34 carb.
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Tony, yours appears to be a '77 as the '76 had the old style forks. '77 had leading axle and I think '78 was the start of the up-pipes. This is only assumption going on a series of pics I have for reference.
(http://i727.photobucket.com/albums/ww272/yumastepside/77H6250.jpg)
.......seems funny that the '77 had leading axle forks but my '80 didnt ?? ??? ??? ??? >:(
Roger
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Sorry Roger, yes mine is actually a '78 model. At least the compliance plate says it is. Still has the low pipe though.
.......seems funny that the '77 had leading axle forks but my '80 didnt ?? ??? ??? ??? >:(
Yes! :D
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serial numbers are 54M08..... and 54M13.......and they have Amals.......
Roger
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..........OK, now we know what everyone has, how about some helpful info. For some reason I keep getting an intermittent spark, checked earths, wires etc. disconnected the kill switch.... same deal......any clues ?? ??? ???
Roger
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Check that the woodruff key on the ignition is Ok. They do shear!
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The woodruff key is only for getting the flywheel in the correct position it does not hold any load. If the flywheel rotates (which it should not) and breaks the key then it only affects timing not the stength of the spark.
I always run a wire directly from the stator backing plate to the coil earth to eliminate the possiblity of a bad earth. You can run a temporary earth wire as described to test the system.
Almost broken wires also create high resistance paths which weaken the spark. Plug gap should be only 0.55mm. I have often found that old crimp connectors look OK but once you cut them off they are corroded internally which also create high resistance
Grab a known good plug and grind the earth electrode off. The Motoplat should be able to create a spark between the centre electrode and the spark plug body when the body is grounded. If it does not then the Motoplate need attention.
Also another unusual problem with Motoplats is that if the bike sits for a long time (years) and depending on where the flywheel stops it can magnetise the stator coils and cause no or very week spark yet after a period of use the spark returns. Ross I can feel you rolling your eyes at this point but TRUE STORY ;D 8)
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Check your coil grounding. Make sure the coil is mounted against bare metal.
Also the the engine has to be grounded, so at least one of the motor mounts
must have a good clean ground to the frame. Replace the plug cap with a new one.
The motoplat's do go bad, but they can be rebuilt.
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Motoplats have a long history of dry joints and/or dead components inside the stator resin - try Jared's and MontyN's suggestions, but don't be amazed if it turns out to be a crook stator.
Either way, it can be fixed at a moderate cost.
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Ross I can feel you rolling your eyes at this point but TRUE STORY ;D 8)
Oh Gawd. Here we go again....... ::)