The Montesa Cota 315 R Thread...

Discussion in 'Trials' started by Garthe, Jul 19, 2009.

  1. motobene

    motobene Motoing for 49 years Supporter

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    Brewtus is a high level connoisseur of many bikes with a certain patina :-)
  2. Brewtus

    Brewtus Buffoonery, Inc.

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    True. I am getting a hankerin' for building a nice one, though. Problem is, I know I'll just go out and throw it up against a rock. Since my Cota 25 donor is so small, I'm making that one a nice build since it's too little to go do serious stunts on. I have other minis for that. :lol3
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  3. skuikka

    skuikka Been here awhile

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    Hello. How many watts does the stator put out on the 315r? Couldn't find the info on the manual. I need to source a new regulator for my new to me -99 Cota.
  4. Brewtus

    Brewtus Buffoonery, Inc.

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    *Sigh*

    Miss Bitters hadn't ridden her 315 for the past couple of years, she's been having fun on her 305 Fantic. She had a hankerin' to ride it this upcoming weekend in the HPTA event, so I dragged it out of it's cubbyhole and fired it up on fresh Sunoco/Motul, rode it around to unglue the Sureflex clutch (:fitz), and generally got it warm and happy. Put it on a stand afterward and noticed this -

    20191112_154333.jpg

    Yup, rear shock just blew it's guts out. :bluduh Oh well, I was ready to have several shocks done this winter anyway. :rolleyes

    Just can't have nice things..... :lol3
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  5. Norman Foley

    Norman Foley Devotee of the Husqvarna Supporter

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    Sign from God to cut back on beer and burritos...... Maybe the more petite Miss Bitters wouldn't have blown the seal head right out!?! :hide :D
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  6. lineaway

    lineaway Long timer

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  7. Brewtus

    Brewtus Buffoonery, Inc.

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    Yeah, I'm sure that's it...... :rolleyes
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  8. Norman Foley

    Norman Foley Devotee of the Husqvarna Supporter

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    Got Bob laughing, which just a dried out seal wouldn’t! :D
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  9. Norman Foley

    Norman Foley Devotee of the Husqvarna Supporter

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  10. Brewtus

    Brewtus Buffoonery, Inc.

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  11. Norman Foley

    Norman Foley Devotee of the Husqvarna Supporter

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    Don't forget to prominently display your packet of Rothmans ciggys and light one upon receiving your trophy! Cool bike!
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  12. Brewtus

    Brewtus Buffoonery, Inc.

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    Blech!! Smoking a Rothmans was akin to smoking a tire. Not nearly as nice as the Camels I used to smoke. :lol3
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  13. ADV57

    ADV57 Adventurer

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    Hey guys! I wanted to share a video I made on how I modified a 4RT rear fender to fit my 315. Hopefully it will help someone. Thanks.
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  14. ADV57

    ADV57 Adventurer

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    I made a video on how I modified a 1996 CR250 FMF Turbinecore 2 muffler to fit my Monty. It took a few months because my TIG welding skills aren't up to par, but I eventually got it done. The bike has a bit more bark on the bottom end with the FMF vs the slip on screen over the end of the OEM muffler. Hope this helps someone.
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  15. motobene

    motobene Motoing for 49 years Supporter

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    Love the 'hope this helps' spirit!

    Great work and video. Very clean looking muffler substitution. Sounds just a bit poppy. I wonder pop abatement is why the original muffler is quite long?

    The 315R is my favorite 'Hontesa.' Wish I had a cherry example of the last year model. Love that 250 engine. Some parts are not easy to find for the 315, however, so videos like this are great.
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  16. Brewtus

    Brewtus Buffoonery, Inc.

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    @LowPSI was doing the Turbine Core muffler adaptation on 315s early on. Nice clean USFS approved spark arresting silencers, if not a bit barky. Every NMTA 315 I ever saw had them, both of mine came with them installed. I found a cherry OE 315 silencer for Roxy's Rat (the Turbine Core was beaten to a pulp), and it has a butt-plug screen in it to satisfy the Dumbest Law Ever.
  17. trials935

    trials935 Been here awhile

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    Yes, I did this also to my 2000 315 to ride the Ute Cup in 2000 to get a USFS spark arrestor, easy to do. (Along with a 280 kit, lightened flywheel, advanced timing, a milled head, aftermarket reeds, and Keihn carb.) Let Chris Florin try it, he was all smiles. Carried 1 liter of extra fuel because of the big engine, didn't know how much it would use, ended up giving a half liter to Martin's buddy Mike Griffiths who had run out on the loop. The next time I rode the Ute Cup, I had the large capacity tank on it. No more carrying fuel in my backpack. Put the original muffler back on soon as I got home. The FMF choked the 280 a little.
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  18. noyolk

    noyolk Certified Preowned

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    Looking for advice on who to sent a shock too for a rebuild. Not in any hurry as I have a donor bike to pull parts from, but now it can not stand up on its own. Thanks.....
  19. motobene

    motobene Motoing for 49 years Supporter

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    I don't do them any more. Randy Lewis out of California may still do them. The Showa is a nice big shock with a lot of potential. If the seals and reservoir bladder are still good (which they usually are), the Showa is a an easy rebuild. The rod threads and nut are swaged over in complete tamper-proofing overkill, but one can grind the edge around the nut to get the nut off to get at the stack to re valve the shock. No Loktite on the nut when re assembling, but if it makes you feel secure, do use it.

    I re valve the Showas because they are notoriously slow, making the bikes they suspend feel dead and heavy. There are a bunch of small diameter shims in the top of the stacks. I use a few of them as lever shims. Speeds them up nicely without getting into wheezy pogoing. And the rebound bypass adjuster then makes sense. Otherwise it's wide open and still too slow.

    Here's my spec, freebie... the right two columns. No new shims required. Pretty brainless. The 315 or latest Showas may be differently valved. You can check yours against the first two columns.
    IMG_20200718_112413.jpg
  20. Vintage pro

    Vintage pro Been here awhile

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    I did one last week and replaced the seal head.
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