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Hi

Now that the Christmas fun is almost over, it's time to get on with the 250 scrambler strip down.
I have a couple of questions.
The throttle and choke assemblies are stuck firmly in the body of the SSI29 carb, does anybody have any tips on how to remove them without causing damage to the carb?
Also I would like to strip down the rear marzocchi shocks does anybody know how to get them apart?
The front forks are half out!, one side needs work on the top bolt which has cracked, and the lower fork leg came straight off, missing parts to be replaced.
The main trouble is removing the black covers and striping the head stock, again any tips would be useful.

Thanks

Rob

The castellated cap of the carb twists off. Probably varnished fuel is holding it in place. The carbs also came with a pin that locked the top on by feeding through one of the castellations, so be sure there is no pin holding it on. It's rare to find them with a pin in place anymore. You might just have to soak the carb in carb cleaner and work at it.

Can you take the shrouds off the shocks? My model doesn't have shrouds and the shocks come apart when you compress the springs. See if you can get the shrouds off.

Once the springs are exposed I use very thick nylon cable ties and cinch them around a pair of spring coils, then I move perhaps 90 degrees around the coil and cinch another pair of coil springs repeatedly until I have enough overall spring compression that the bottom of the shock is loose from the lack of spring pressure and the thing just comes apart.


Jim

Do you have a shop manual? if not you should buy one. there are some manuals in the "Tech Section" on this site but it is hard to look at manuals online.
there is also a lot of information in the tech section and the Links section you should look through.
here is a link showing how the shocks come apart. the jig is totally unnecessary, and can be replaced by a set of helping hands.
just turn the shocks upside down and push down hard, work the two cups apart and dislodge the ball bearings. the balls are the only thing holding them together.
http://www.mts.net/~jkrocker/Duke2.5/

once you get them apart, the body of the shock has a cap that unscrews. the cap holds the seal for the dampener rod.
depending on when your shocks were made they could have slightly different internals, and different size seals.
once you get the dampener assembly apart remove the oil seal. there is a steel disc that covers the seal. if it has a hex hole it unscrews,
if it has a round hole it is a press fit.

I've taken apart several SSI carbs and everyone one of them has had parts frozen together, they can be difficult to get apart due to corrosion.
the best tip i can give you is whatever you are trying to get apart you need to be able to hold the carb body firmly without damaging it.
what I use is two wood boards spaced apart a few inches and screwed together, so that the carb will fit between them at different angles.
this will keep the carb from rotating while you are trying to unscrew something and avoid the need to clamp it tightly in a vice.
this trick has worked for me without fail on multiple SSI carbs.

good luck,
Aaron

I just recently stripped down a 250 Scrambler myself. The black fork shrouds unscrew from the bottom of the lower triple tree. Once you pull the fork tubes and springs out, look up into the covers. There are flat head screws holding them in place. You need a long screw driver. My advice is to download or buy a manual and some penetrating oil.

Cam

[quote= RobertVine ...
" The throttle and choke assemblies are stuck firmly in the body of the SSI29 carb, does anybody have any tips on how to remove them without causing damage to the carb? "

____ Yeah, it's not very uncommon for the throttle-slide & the (often so-called) choke-plug to become stuck in their respective bores (after having been left for extended periods of non-use outside in uncontrolled weather conditions).
__ Before trying-out the most drastic version of the following method-steps of unfreezing & separation, you should FIRST try-out rather milder method-steps (that are sequentially less likely to yield success). ...
Have you yet tried-out merely warming-up the carb.body (within a toaster-oven, for example), and/or left it's bore-holes soaked with some sprayed penetrating-oil ? _ If-so or not, you next need to thoroughly spray/dose those bores with a good penetrating-oil while the carb.body is somewhat warmed-up (near to normal operating-temp, and-also perhaps with the oil-spray rather cold), and then see if either stuck part can then be budged-loose from their stuck positions (while the carb.body is either at room-temp or warmed-up again).
If still no-luck, then you probably need to try another dosing of thin-oil with repeated cool-off & heat-up periods, with each successive-try heating the carb.body to a higher temperature after having had a still deeper cool-off -(after a room-temp trail,, then refrigerator-temp, then-next freezer-temp trails), so as to hopefully shock & break-loose the stick-grip between the stuck parts & their bores.
Now if none of those (gradually increased) temperature changes (along-with additionally added penetrating-oil) help-out with getting those parts loosened-up, THEN you can next try the most drastic method-step (which has never failed to do the job for me)... and that's to take the COOLED-down carb.body and quickly dunk it down-into boiling mineral-spirits, then pull it out (after a time-period of your-own choosing -[either a few seconds, or a few minutes] ), and find that those stuck parts are no-doubt THEN willing to budge-loose and more easily become worked-out & apart.
If STILL no-luck (at getting either stuck part to budge), then rather than giving-up, I'd suggest keep-trying this exaggerated method over again (rather cooled-down from a freezer, at this advanced point), at-least until four more attempt-tries (with alternated period-lengths of soaking-dips/dunks in the boiling mineral-spirits) has still failed to get those stuck parts even slightly loosened-up. _ (But I'm pretty-sure that the job will have worked-out some-time before this fully extreme point).
__ Next,, while I-myself don't have any experience with such, I've heard that a 'sonic-bath' within pure-H2O (with or without alcohol added), can get a carb cleaned-up of the corrosion which causes carb.parts to freeze-up,, and-so THAT-method may possibly work-out for you.
__ BTW, while I haven't found such instance to be a common occurrence,, I can't promise that none of the SSI-carb.body's thin outer plating/finish-coating won't flake-off at all (like some extra-strong carb.cleaning solutions can possibly do), due-to either of the two main method-types I've covered.
____ Please let us know whatever method-procedure you've tried-out to free the stuck parts, and how well the chosen processes performed for you.


Hopeful-Cheers,
DCT-Bob

Thanks for the hints tips and information.

The carb still has the locking pin in the castellated nut, both of which have been removed but then lightly screwed back in place to get some plus gas and carb cleaner to it.
I will continue with this for a while until moving on to Ducati Bob's methods.
I should be able to get the rear shocks apart following the guide the guide forwarded by Aaron.
I will also continue with the front forks.
I'm using the shop manual that's viewable on this site, whilst I source a paper copy. The tips from everybody are a real help, as the last thing I won't to do is break something that's hard to replace.
Thanks again, I will keep you posted on the progress.

Rob