Hey all,
Brand new to this form and the only reason i'm posting so quickly is because i've searched for information on the trek 790 and have found very little. I bought a used trek 790 multitrack frame, fork, stem, headset and square taper BB (all complete) for $198. I'm turning the bike into a medium to heavy touring cycle for a 600 mile ride through alaska this summer. Any information on this bike would be helpful, and since i'm new to touring, i have no experience bulding a touring specific bike. I've purchased a brooks b17 saddle and thats it. Looking at all other components now. Help me out!

Welcome to the forum! Are you sure it's not a Trek 970? If so, it is an excellent non-suspension mountain bike - pretty high up in the Trek food chain in those years (89-92 or so). Way lighter than the more common 800 and 850. They have a nice lugged steel frame with great components. The only drawback I found was because they occupied the performance end of the spectrum they have a fairly long top tube and low bars relative to saddle height which I found uncomfortable for long rides. You can mitigate it to some degree with a higher stem but I never used mine much for touring although I still use it to bomb around on and have the racks and such for it. Plan on going through it carefully, but basically you have a good bike to start with assuming you can deal with the ergos. If yours is in fact a 970 (not a 790) let me know and I can help you out with pics and/or details as mine is still very original.

*EDIT* I went out and looked at mine and see it is a "Singletrack", not "Multitrack". Sorry, guess yours is in fact one of the hybrid series they made. Curious if it's steel or Aluminum? Good luck with it.

The Multitrack 790 sat at the top of the hybrid range in 1990. It was built with True Temper cro-mo steel so it should work fine as a tourer. There's a 790 on Velospace fitted with bags:

The frame is a 790 multitrack, red like the one above. It should be getting to me this coming week sometime from ebay and i'm itching to start bulding the bike up. I've been looking at wheels but, without the frame, i don't know the dropout spacing. I'm thinking either: 700c rhyno lites w/deore xt hubs or mavic a319's w/ deore xt hubs. Just need to know what width hub i need. Also looking to upgrade the square taper bb to a isis or splined (is this possible?) I've heard that square taper bb's last longer if properly maintained....? Looking at deore deraileurs. XT casset and crank. I'm confused on breaks. Linear pull or cantalever? The only other important upgrade i was gonna make would be a new canecreek 100 headset for the 1" steerer tube. Any info on these ideas would be really appreciated. thanks! pictures soon once things start to arrive.

https://cgi.ebay.com/ws/eBayISAPI.dll...#ht_500wt_1156

I hope you can see this is the frame i bought

Personally, I'd stick with plain Deore hubs. It seems that XT hubs are not what they used to be and either bearings and freehub bodies are prone to failing too soon: https://www.crazyguyonabike.com/doc/p..._id=75023&v=3b

thanks for the input. does anyone know the rear dropout spacing? what size hubs can i run?

XT hubs were either 130 or 135 mm, so possibly DX were the same. If you decide to go for a modern MTB rear hub, I'm sure the steel frame can accept it without any problem.

I have a 92 790 and the rear hub spacing is 135mm.

so the frame came in today! looks great, will put up pictures tomorrow. Measured the rear hub spacing and it's 135. I'm eroiusly looking at a mavic a319 36spoke w/deore lx hubs. I'll be using the bike primarily as a commuter but am planning a heavy touring trip for june. The wheels all built up will cost me around $230.

Also, do i need a medium or long cage deraillieur?

Probably, long, if you are going to put a small Granny gear on , 24t on 74mm bcd.
the chain tension slack has to be taken up somehow.

Regarding brakes: I prefer V-Brakes to cantilevers because they're simpler to set up for solid performance. I had a problem on my last road tourer with a V brake cable impinging on the bike's fender, so I had to go back to canti's on it. However, the V brakes I tried were Tektro Mini's with pretty short arms, and it likely would not have been a problem with a longer armed MTB type v brake.

Regarding BB's: It's possible that a square taper BB will last longer than modern external BB's, they are inexpensive and durable and there's really no reason not to use them. I've had no issues with external ones though. My advice is to decide on a crankset you that suits your needs and get the BB that suits it.

Since you have a bare frame with what sounds like little use, if you are lucky to have no or minimal rust inside, it would be a good time to preserve that nice frame by treating it with Boeshields, Framesaver, engine fogging oil, or any rust inhibitor. Something is better than nothing.

Enjoy the build of course you will post a pic when it's done?

I have a 90 750 which is the same frame as a 790. It has the same geometry as a 520 with slightly shorter chain stays. I built it as a commuter and long weekend tourer, before tearing it down and building it back up as an around town and grocery getter. Here is a pic of her mostly complete as a tourer.

Actually, CS length on your 1990 750 is the same as the 1990 520 and even the mtb frames, specifically 43 cm. The longest CS frames Trek made in 1990 were their least expensve 800-series mtbs, at 43.7cm.

If you compare your frame geometry to the 520, you'll see they're nearly identical.

https://www.vintage-trek.com/TrekBrochures.htm

https://www.vintage-trek.com/TrekBrochure1990.htm

BTW, the OLD spacing on my 1990 950 frame (same as 970, 990) is ~132mm. IIRC, 7-spd MTB freehubs were spaced to 130mm.

My bad. Was comparing the chain stay to my 2004 520.

So it's been a couple days and the frame arrived.

Everything looks good. After measuring the spacing 100mm Front and 135mm Rear. Based on these measurments i ordered some wheels. I went through prowheelbuilder.com Anyone have any experience here? What i built up custom are: Velocity Dyad 700c w/ shimano xt hubs. 36spoke 4 across w/14 guage spokes. alloy nipples and rim tape. Total package delivered ran me $330. i could have settled for less expensive and pre built wheels but I'll be skimping on derailleurs, the bar, stem, seatpost. saving money on items that only get more expensive the lighter they get.

So some new questions. The difference between deore cranks and deore xt cranks is a little over $100 and could i go used here? Is the only real difference weight? I'm thinking i'll go full shimano as they will be easier to find parts for than Sram. Basically i'm building the bike with complete mountain components. Any suggestions on a BB upgrade? More to come when wheels arrive!

If you are looking for an outboard type of crankkset, this is a pretty hard deal to beat:

https://www.jensonusa.com/store/produ...+Crankset.aspx

I installed this on my Fargo and no complaints.

I still prefer a Sugino square taper or equivalent for touring. Something like this:

https://www.jensonusa.com/store/produ...Cranksets.aspx

Shimano no longer makes a high quality square taper BB but you can still find UN73/74s on ebay or go with a VO, IRD or Tange. Lots of good options.

Why did you go with straight gauge spokes?

After researching the 2011 xt line up im a little bummed i put that hub on my bike. It sounds like there have been better results with deore components. As for the straight gauge, i really have no excuse other than they came in blue an i thought it would look good with the red. This will be my commuter after the trip more than anything. That whole set up may be a downfall.
Hopefully on a better note everything else is in the mail. I made a spreadsheet on excel with the budget to date.

Part Description Price
Frame 1990's vintage used Trek 790 touring frame w/fork. 100mm front spacing. 135mm rear spacing. 1" threaded headset. BB 68mm?? Seat tube 27mm internal 31mm external $198
Saddle Brooks B17 Special $129
Wheels Velocity Dyad 700c w/ shimano xt hubs 331
Brake levers/shifter Shimano Deore with cables (no housing) 39
Crank w/bb Deore lx 22-32-44 170mm 89
Cassette Shimano Deore 9sp 34
grips Gravity lock on 16
Headset Interloc 1" threaded and sealed 65
Tires Continental touring plus 700c/37mm 68
Tubes Q tubes presta tubes 700c 35-43mm 14
Racks Rear Civia Hyland Steel 50
Rack Front
Panniers
Front Deraillieur Shimano Deore 35
Rear Deraillieur Shimano LX m581 49
Fenders sks p45 39
Chain shimano cn7701 9spd 32
Brakes (rear) Shimano Deore m590 22
Brakes (front) Shimano Deore 22


Total $1,232
*all shipping cost included.

So how did the build turn out?

That's my 790 that some one posted above.

Hey all! i totally forgot about the thread until you posted and they sent me an email! thanks for the inspiration with your build on the 790! it looks amazing. My bike turned out phenominal and i catch compliments on it every where i go. Someone even offered to buy my bike while i was in Denali! haha. Here's a pic. she's my daily rider/commuter and has been amazing. So strong i take her off curbs and stairs without hesitation.
<a href="https://s1186.photobucket.com/albums/z362/mse871859949/?action=view&amp;current=P7040828.jpg" target="_blank"><img src="https://i1186.photobucket.com/albums/z362/mse871859949/P7040828.jpg" border="0" alt="Photobucket"></a>
<a href="https://s1186.photobucket.com/albums/z362/mse871859949/?action=view&amp;current=P7040827.jpg" target="_blank"><img src="https://i1186.photobucket.com/albums/z362/mse871859949/P7040827.jpg" border="0" alt="Photobucket"></a>
<a href="https://s1186.photobucket.com/albums/z362/mse871859949/?action=view&amp;current=P6150752.jpg" target="_blank"><img src="https://i1186.photobucket.com/albums/z362/mse871859949/P6150752.jpg" border="0" alt="Photobucket"></a>

oh rats, sorry that post didn't turn out. my pictures are on photo bucket. i guess if you upload the links you can see them. also, our blog from the trip is Findingthewaysouth.tumblr.com

https://s1186.photobucket.com/albums/z362/mse871859949/

Fantastic thread!! I'm getting ready to do the same thing with a 95 Trek 730 that I bought new, way back when. I'm starting with a complete bike and will likely keep a few components (ie, deraillers, brakes, handlebar) unless a mechanic says I need to replace them but wheels, crankset, cassette, shifters, seat post, stem and saddle will all get replaced. I also plan to get the frameset powdercoated, either a bluish-gray or dark orange. I have to get the bike back from my parent's house but I can't wait to start the project and get back to riding steel!