c0rbin9

Found it, its 26.4. Measured by a bike shop and engraved on the steerer tube. Thanks all.

If anyone is needs this info, the 1990 Trek Multitrack 750 takes a 1" threaded headset with 26.4 (ISO) crown race/steerer tube measurement.

mechanicmatt

mechanicmatt

hokiefyd 

That 750 looks great! It's hard to beat the Conti Speed Ride tires.

Powerman

Great looking build!

Powerman

Nice!

What brand wheels are those? I like them.

Powerman

Nice! Where did you get the components (bars, stem, etc.)?

Powerman

Thanks.

fujifinest

After lots of reading, I am torn between the Trek 730 and the Specialized Crossroads. Anybody own both or have comments on the performance of the two bicycles?

I notice the Trek 750 has lugs on some pictures. This must be an earlier model as I also see welding. When does the change take place?

What hybrid bikes were made out of steel?

DorkDisk

93 was the last year Trek used lugs; pre '99 would have a large percentage of steel frames.

dmark 

7xx models are steel; 7xxx (4 digits) are aluminum hybrids.
I have a 750 so no comment on 730 vs Spec.
My daughter has a '97 730 and I like it as does she.

OldCruiser

I’ve had this frame for several years . I bought it at a yard sale stripped it because the previous owner had trash it . But I thought I could build something out of it someday. I think it’s a 1995 .
I started on it yesterday afternoon and finished it up this morning using some old , some new on hand parts .
I wanted to see how it rode and felt before putting more money into it .
It only has a front brake for now , I’ve ordered a cheap set of V-brakes to put on it . Wanted Shimano , but they were either out of stock or over priced.
I like the bike a lot . It rides smooth and maybe the fastest in my stable of bikes . Feels light .
After the brake overhaul, I’ll ride it for awhile before I order anything else for it .

Mogens

We have 3 multi-track 730s in our household and the 1995 has the best riding frame.

Powerman

What's your drivetrain setup?

Sailing

I am new to bikes but just bought a Light Blue 720 which seems to rack me every time I come to a stop as it seems to tall for me. There are no markings on it that I can find to tell the size. I am 5’8 and wish this was a couple inches shorter. Is there another way I can find the size of this bike. I do love riding the bike but have started looking for another multitrack maybe 17-19”?

OldCruiser

32 tooth single narrow wide chainring, 12-28 rear cassette.
I swapped out the cranks for Shimano 175mm square taper hybrid crankset with removable chainrings.

l3m4nt

Any ideas on what the clearance/max tire width is on the 720? If all goes well I'm picking one up tomorrow.
Would post a pic ... but first I need to reach my 10 posts
BTW, I registered the site thanks to this topic.

mtmann

I have 3 Trek 750s (All lugged US-made) and a Specialized Crossroads (tig welded Taiwan Made). The 750s were lugged 1990-93 (4 years). All tig welded 700 series hybrids are post-93.

the Crossroads is a little “livelier” feeling, while the 750s tend towards a more stable, touring bike feel. My Treks have mid-fork non-threaded eyelets, making them better for carrying overnight gear, while the Crossroads lacks these. It does have a threaded fender mount on the seat stay bridge,with room for a fender AND a kickstand without interfering with the front derailleur cable. You couldn’t do that with the Treks.

Mike M

Powerman

Your setup looks good.

ja1124

I've ridden steel Multitracks and steel Crossroads and have found the rides to be similar. All the Crossroads frames I have seen were 100% chromo. Not all Multitracks are 100% chromo. The steel Giant Innova is also similar to the Multitrack and Crossroads.

Powerman

I don't know if the frames are marked. My 1993 700 isn't. But, you can measure the distance between the top of the seat tube and the middle of the bottom bracket. That should get you pretty close. Generally, 19" is a large, 17" is a medium, and 15" is a small. Trek offers some mid-sizes on their current bikes (ie. 18.5"), but I don't know if that was true on the older ones.

hokiefyd 

The MultiTracks were also offered in 21" and 22.5" sizes. My '97 750 is a 21", and the center-to-top measurement is right at about 54cm.

l3m4nt

Picked up my 720 today, will post a picture in the next few days. The serial number is very hard to read (and the previous owner doing some spray-painting on the frame did not help :/).
I did some research regarding what I could make of it, but no match so far. Is there a site where you can just enter the nr?
Also, there is a second series of characters. This what I found (but like I said, hard to read, so not 100% sure)
T2C005057
BI0407
Regards, and thanks for all the inspiration in this thread.

hokiefyd 

Vintage Trek (.com) has some good information for you. Here's a direct link.

That serial number suggests a Taiwan-built frame from, perhaps, March of 1992 (if the information there is accurate).

l3m4nt

Thanks, you're probably right. I had already checked some catalogues as or 94, 95 etc. but seems it's a bit older.
The color-scheme could match the 720E (European-only-model). I took some of the red spray-paint of today as a test, and it appears there's black underneath.