80s, not 70s!
Shimano Positron Indexed 5 Speed Derailleur. Operated by a non indexed shifter with a steel wire instead of cable. Very cool stuff from the 70's.
Yes, those "frankenstein" systems work perfectly when new. I see a lot of them since I started a full-time job in a bicycle workshop (even new bikes, like a combo shifters-Altus, front derailleur-Alivio, rear derailleur-Deore XT), but only when new. When something starts to wear (like shifter for example) and everything won't even try to work. A week or so ago there was a guy who had the same problem as you - whole bike on Deore from group M591, except of the rear derailleur - an SLX M622. Everything from year circa 2012. The derailleur wouldn't want to work with the Deore shifter. New cable? Nah. New outer casing? Nah. New shifter? Nah. The only solution for the problem was to order a new rear derailleur from the group Deore M591.
On the other hand I have a client who has a complete set of Deore XT from about 2010. The whole set made +- 38000 miles of heavy beating, and it fails to shift properly cause the shifter is used up. But still the problem is that you have to "overpush" when shifting up, not that the derailleur shifts like it has a mind of it's own skipping two or more gears.
The Rock Rat
- Thread starter MattiThundrrr
- Start date
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The Positron works with the Shimano Front Freewheel System because the it is less likely to push into the fixed freewheel when it is moving downhill. The coasting is in the chainrings and the 5 speed freewheel is fixed.
Shimano Positron Indexed 5 Speed Derailleur. Operated by a non indexed shifter with a steel wire instead of cable. Very cool stuff from the 70's.
Yes, those "frankenstein" systems work perfectly when new. I see a lot of them since I started a full-time job in a bicycle workshop (even new bikes, like a combo shifters-Altus, front derailleur-Alivio, rear derailleur-Deore XT), but only when new. When something starts to wear (like shifter for example) and everything won't even try to work. A week or so ago there was a guy who had the same problem as you - whole bike on Deore from group M591, except of the rear derailleur - an SLX M622. Everything from year circa 2012. The derailleur wouldn't want to work with the Deore shifter. New cable? Nah. New outer casing? Nah. New shifter? Nah. The only solution for the problem was to order a new rear derailleur from the group Deore M591.
On the other hand I have a client who has a complete set of Deore XT from about 2010. The whole set made +- 38000 miles of heavy beating, and it fails to shift properly cause the shifter is used up. But still the problem is that you have to "overpush" when shifting up, not that the derailleur shifts like it has a mind of it's own skipping two or more gears.
So the chain or derailleur does not destroy itself, each cog on the 5 speed freewheel moves separately, but there is a lot of friction in the movement in each cog, so the freewheel is still mostly fixed gear.
MattiThundrrr
Rattus All Terrainus
Whatever the heck that is, it ain't going on my 'Rat. I outgrew five speeds decades ago
Thanks for correcting!
Be prepared for a suprise in this year's Build-Off
MattiThundrrr
Rattus All Terrainus
And now, back to my bike!
Finally got off my buttons and made it across the border to get the gear. Thanks to @irideiam for the goods, I'm so excited to get them on the Rat!
Now I really gotta get the rest sorted, I'm so excited to ride, I might end up doing it with a cruiser fork and no gears!
As promised...
Finally got off my buttons and made it across the border to get the gear. Thanks to @irideiam for the goods, I'm so excited to get them on the Rat!
Now I really gotta get the rest sorted, I'm so excited to ride, I might end up doing it with a cruiser fork and no gears!
MattiThundrrr
Rattus All Terrainus
I entered the Rat in the RetroBike Bike of the Month contest, Blue Collar Edition. It's actually getting votes!
http://www.retrobike.co.uk/forum/viewtopic.php?f=1&t=407062
http://www.retrobike.co.uk/forum/viewtopic.php?f=1&t=407062
Your description of constant abuse has rendered your baby toast. Since you have history with it and want to be buried with it, just rebuild it and get it back to original. Shifters, derailleurs, rear cluster, rings, chain along with any other moving part, perhaps even the wheels themselves when high-mile is not good. Maybe consider replacing all of it with low-mi stuff you can find for almost nothing. Bummer about your early Rock Shox Mag21, the fork that changed everything..
For your build here, it is too bad you don't have another bare frame you could start fresh on. These frames last a long time. I would load one up with a weather-proof 3-spd igh and drum front, 1" threaded to thread-less stem conversion leading to a myriad of fork options.
For your build here, it is too bad you don't have another bare frame you could start fresh on. These frames last a long time. I would load one up with a weather-proof 3-spd igh and drum front, 1" threaded to thread-less stem conversion leading to a myriad of fork options.
MattiThundrrr
Rattus All Terrainus
Threw a little bit of flat black at a few parts... Irony: took me two decades to finally paint over the blue anno bar ends, the day after I do it, I bring home another bike with a set that I want to use instead.
MattiThundrrr
Rattus All Terrainus
Here's the stuff that might wind up on the Rat. Grips and cute little horns:
MattiThundrrr
Rattus All Terrainus
SEPARATED AT BIRTH!!
Saw a listing, thought I'd share. This must be what my rat looked like as a baby!
I wish I hadn't tossed the bars and that seat, mine ripped in the exact same spot. Never kickstand!
Strangely, the pedals on the above bike look like the same wellgos that I found in the trash and used on mine for the last few years.
The truly crazy part is that bicycle store sticker, that's the LBS where I have taken mine to for service since the ninties! My special lady friend even had a job there.
I wanted the bike just for the history, but I think RockRat might have been jealous
Saw a listing, thought I'd share. This must be what my rat looked like as a baby!
I wish I hadn't tossed the bars and that seat, mine ripped in the exact same spot. Never kickstand!
Strangely, the pedals on the above bike look like the same wellgos that I found in the trash and used on mine for the last few years.
The truly crazy part is that bicycle store sticker, that's the LBS where I have taken mine to for service since the ninties! My special lady friend even had a job there.
I wanted the bike just for the history, but I think RockRat might have been jealous
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Those Hookworms look BEEFY on there!!!
Thanks , I love Hookworms ! They are my favorite tire . They’re heavy but roll great once you get them going and they grip like no other tire I’ve ever used . And they Work like shocks absorbing bumps .Those Hookworms look BEEFY on there!!!
I have an updated version, a 2020 Rockhopper turned into an urban assault bike .
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Do this @MattiThundrrr
MattiThundrrr
Rattus All Terrainus
MattiThundrrr
Rattus All Terrainus
So I bought this last week...
2010 Hardrock. Kinda renders RockRat completely obsolete. I've only ridden it a bit, but it does everything better. And Ms Thundrrr says I would have to be crazy to take everything off of this and move it to sn older, rattier frame. So I have some decisions to make...
MattiThundrrr
Rattus All Terrainus
I actually bought two. One is hers, and she said I could get rid of her old gt. I think that's a little cold hearted. RockRat ain't getting sold.
Everybody chanting........
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
Swap the parts
I think she has a point.
Keep the new one as is, that way when she wants to for a ride with you your response isn't "well I just have to reattach the thingamajig, and none of my other bikes are rideable right now"
Now you can take your time with RatRock and do it right, save up for the parts you want, not what you can get your hands immediately, you've got another 20 years now.
Keep the new one as is, that way when she wants to for a ride with you your response isn't "well I just have to reattach the thingamajig, and none of my other bikes are rideable right now"
Now you can take your time with RatRock and do it right, save up for the parts you want, not what you can get your hands immediately, you've got another 20 years now.
