Kev5171

Hi all, my first post here!

I have an old Trek 810 ST 21 Speed
It's well worn but I still love it, so even though it's probably not worth the money I still want to fix it up.

Can anyone tell me the exact specs of the parts I need to order if I want to replace the:
- Front chain rings (whole crankset?)
- Front derailleur
- Rear cassette (although I suspect it's a freewheel)
- Rear derailleur
- Chain

Are they all super specific or can I use generic parts? Which ones?
Thanks!

Bob the Mech

So you are looking to replace the entire groupset. The Shimano Altus M2000 groupset is probably a cost effective upgrade or your old system. It sits above Tourney. Things have moved on a bit since your 810 was made. Even the entry level Altus is now 9 speed. It isn't going to be cheap...not that it's expensive in the grand scheme of groupsets...but getting it all at once...and buying a new rear wheel. If you look up the Shimano web site there a whole world of info on groupsets from 7 speed all the way to 12 speed.
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DrkAngel321

Stumbled onto this...I had the same bike. It was stolen in 1993. I purchased it sometime between 1986-1987 I believe. I wish I can find another. Would you happen to know what replaced that one?

Darth Lefty 

Over the early 1990's when mountain bikes started growing suspension forks, bike companies started making hybrids with the same posture, gearing, and all the same convenient frame features, but skinnier road bike tires. The Trek model was the 700 Multi Track. Today's closest descendant would then be the Trek FX. The Marlin is now the entry level mountain bike but I don't think you'd find it much like an 810

bloomjbikes

I have a silver Trek 810 17.5" frame with 3x7 drive train that is in good condition overall. However the wheels aren't great and the shifting is starting to get nasty. I'd like to do a mild rebuild to include wheels and derailleurs / shifters and cables. How do I figure out what wheels I need to buy and can I transfer the cassette or am I better off buying new? I'm not a bike mechanic but I think I can do the disassembly/reassembly if I can identify the right parts.

What is the best way to develop a parts list? The wheels seem to be 27" but I'm not sure what standards they are, etc. Right now it has 37-622 tires. I'd like to buy wheels that allow the widest offroad oriented tire the frame will accommodate.

I've googled but I'm not finding much detail on the 810.

Trav1s

Honestly, this would be best posted in Vintage/Classic or Mechanical secton. I hope mods split off your post into a new thread.

Are you somewhere other than the USA? From everything I can find, the 800 series is a steel frame line and was available with many different levels of components. Higher number bikes were build with better components with 850 and 890 at the top. The entire 800 series line has 26" wheels and all of the 810s I can find online have a suspension fork.

So the 37-622 (35x700C) tires are a surprise to me.

Yes you can upgrade it if you desire. I see it's a DIY project? What are the components on the bike?
- front derailleur
- rear derailleur
- controls (likely SRAM twist grips and probably red)
- Freeheel or freehub wheelset (wheel type and hub information)

All necessary to figure out replacement parts since I can't find model specifics while searching the interwebz.

bloomjbikes

I agree what you're saying. Yes it would be a DIY. several years ago the front gripshift failed so I bought one online and replaced it. It came with SRAM MRX shifters. The tires are ones I also installed at that time. I don't recall the original tires. I assume it is a freehub but am not certain.

bloomjbikes

So I can't tell you why but I goofed up completely on this old Trek. Its a 700 Multitrack not an 810. That's what going from memory will get you. oops! I will look into it further in the vintage section.

Trav1s

Well you're in luck! I just rebuilt a curb find 730 Multitrack and you can see my project here: https://www.bikeforums.net/classic-v...n-wettrek.html

The 730 is essentially the same bike with higher level components and a full CrMo frame. Please feel free to ask any questions about the project as I learned a bunch along the way. The end result was worth the effort - it's smooth, comfortable, and easy to ride plus has a great modern drivetrain.

What color is yours? This is from vintage-trek.com

bloomjbikes

Trav1s Thank you for the insights and the link to your 730 rebuild thread. I was going to upload pictures of my 700 but I don't have enough posts yet. According to the list above it is a 1998 - Silver/Red decals. It was my wife's bike during her college years. In decent shape but the shifting is not good. I hate gripshifts anyway so I want to do a minor upgrade build to include shifters derailleurs, and new bottom bracket. My goal is to make it a very nice bike path / 1/2 decent light duty trail/gravel use bike. I'm willing to spend a few bucks to do this but want to keep it in check. The ergonomics seem great to me. handlebars, etc.

I have plenty of tools from my car hobby but no bike speciality stuff so I don't have the tools to remove the crank, bottom bracket, etc. I welcome your direction in picking out the basic tools I'd need to make this happen and identifying the components.

I assume I'll do a chain and all new cables while I'm at it.

-Tools required for bottom bracket, etc.
-Shifters
-Derailleurs
-Chain
-brake cables
-derailleur cables
-grips

-The wheels aren't perfect but not annoying to ride. If I could upgrade them from the weismann 519's for reasonable money I'd consider it
-How wide of a tire can I run in this frame?

Trav1s

Great resource:
https://vintage-trek.com/trek-fisher-klein-lemond.htm

Sales brochure that site:
https://vintage-trek.com/Trek-Fisher...d/1998trek.pdf






Spec manual from that site:
https://vintage-trek.com/Trek-Fisher...manualTrek.pdf

Trav1s

I'd suggest copying this discussion into a new thread in the Classic/Vintage section so that the Multitrack fans see it and more easily chime in. While there is some overlap, this is would be better over there in a NEW thread.

There a many options available for square taper crank removal out there. You will need the crank arm removal & bottom bracket removal. I went with a Park Tools crank remover and a generic BB removal tool from Amazon. Others may have suggestions for you. I'm a car guy and choose to spend the money on good tools. Don't forget a good cable cutter - Park tool seems to be the best with this one..

Easiest thing to do is purchase new front/rear derailleurs and stick with the 3x7 setup. While doing the chain, I'd also replace the cassette and start fresh. Are the cable housings good? You could just install new cables and lube the housings when doing the install. If you can find a set of standalone shifters, install them with new cables and set everything up.

I'd stick with original wheelset for now and install new tubes/tires. I know that 38x700c fit with easy but don't have experience with it. Try a google search for tire fitment on Trek 700/720/730/750 Multitrack. My 730 arrived with 38s on it and I went with 35s because that I what I had on hand.

bloomjbikes

Thanks for your help. I’ll repost.

Trav1s

Ill share stuff over there too.