RRJohn

Hi All,
New guy questions. I just bought a 1985 Trek 620 and the original wheels need some attention. I am OK with the 27" set up but what should I expect to pay for a decent set of used wheels with a different hub than the Helicomatic? For now, I will replace the bearings in the hub but curious as to what another set would cost. Let me know if anyone has something to sell. Also, besides tire selection, what are the advantages of 700c wheels that everyone seems to go to? I'm more of a 'ride it as is' than 'let's change this' person but sometimes an upgrade is in order.
Thanks in advance for your input,
Robert

Duo

i have the same issue, eventually thinking of just replacing the old wheel with a new 27" wheel. not many quality new ones left, but it may be possible to find used or just buy an old bike for parts.

we really need a good thread on the 27" wheel issue regarding what to buy or expect. maybe you can start one?

rustystrings61 

Allegedly, 700C wheels accelerate faster - but if you're not a racer or pretending to be one, it's a pretty miniscule difference. And they're marginally lighter, but when comparing 36 spoke wheels to 36 spoke wheels, the accent is on the word marginal. We're talking 8 mm difference in diameter.

Yeah, there are more 700C tire choices than 27 - but again, if you're not a racer, and not out to do some extreme thing, then the odds are pretty good that a Panaracer Pasela will work beautifully for you, or its puffier brother the Sand Canyon 27 x 1 3/8. There are other 27-in wheels out there, and you may decide you like 1 1/4 or even 1-in width tires - but beware of straight-walled rims - more on that below.

Velomine.com has these 27-in wheelsets with sealed bearing hubs and Sun CR-18 rims currently for $140, which isn't bad for a new set of wheels.

Vintage stuff, depending on condition, can be cheap, but you have to consider exactly which rims you're getting. I've been running assorted Weinmann, Araya and Ambrosio (!) 27-in straight-walled alloy rims the last couple of years on assorted old bikes. With Pasela 27 x 1 1/4 at 70 psi I'm not measurably slower than I am riding Pasela 622/28s at 90 psi, which is good, because to go above 70 psi you really need a hook-bead rim of some sort. In the near future I am going to see how well the same tires work on a set of 27-in Mavic Module E rims, which were apparently the original hook-bead rims, and I'll probably experiment with tire pressures as well.

No joke - after watching the renaissance of 650b, then its transformation into 29.5, I'm thinking the 27 x 1 1/4 is due to be reborn as the Dirty 630, the champion of world travelers, the tire of choice for rides from the Arctic Circle to Cape Horn, or through the Darien Gap, or thousands of cyclists crossing the North American Continent. With its larger diameter, once in motion it rolls over bad roads smoother and easier than its smaller cousins. You can see where the ad copy would go from there ...

RRJohn

Great info, many thanks! I currently run the Pasela’s on my Fuji and like them. Agreed that the 27” is a great ride and my weekend trips are usually asphalt but the Pasela’s can handle gravel. I hope to have good luck with the Helicomatic hub and save the money for a good front rack.

jlaw

Hard to say what you pay for used 27" wheels - many factors involved. You might find a good deal on something decent on Craigslist or ebay. As mentioned, Velomine is another source.

There is also a Classic and Vintage sales page on the BF site that is very active.: https://www.bikeforums.net/classic-vintage-sales/

I have a 1984 Trek 620 that had the Helicomatic hub. I happened to have an old Maillard hub (made by the same company) that had the exact same housing dimensions as the Helicomatic - but took regular-sized bearings and a standard freewheel - you could check with you local bike shop just to see if they might have one. If so, you or the LBS could substitute the Maillard hub and rebuild the rear wheel using the same spokes and rim. I wouldn't bother with this is the rear rim and spokes are not in VGC.

Re: the 620 with 27" wheels - I'm not sure that I'm happy with the original 27" wheels. Mine are in VGC with new Panaracer tires,...the ride is comfortable but a little blah. I may try a new drive train at some point - maybe the wheels have nothing to do with my overall opinion.

If you decide to go 700c and you have canti brakes, I suggest that you test fit a 700c wheel on the front and back to make sure that the original Dia Compe (if you have original) can be tilted down slightly to make-up for the 4mm difference in radius.

Good luck!

ryansu

27" Wheels are available from a variety of sources - Velomine as mentioned above, I have ordered Wheelsmith wheels off of Amazon for a cheap option but they are alloy, QR, stainless steel spokes etc. I do find that you need to adjust the hub as they are misers with the grease and adjust them too tight IMHO. Nothing a few minutes with some cone wrenches and a grease tube won't solve. Velo Orange has some nice 27" as well.

Note if your 620 has Canti brakes then switching to 700c could be problematic for brake reach, best to test with a 700c wheel before making the swap.

Do you have pics of your new Trek?

dddd

The Titan-T rims were of excellent quality, sort of a singlewall "twin hollow" hybrid design and heat-treated. Easily as good as the time-tested Mod58 rims.

I re-laced my 720 rear wheel onto a Shimano 7s freehub, I re-used the original generic spokes, which were of excellent quality and lasted many years of commuting.

The best-shifting chain that I have used with the narrow-spaced Helicomatic freewheel is the old Sedisport chain, but compared to a Shimano freewheel the shift quality is not as reassuring when shifting fast while trying to maintain power output.

700c rims will somewhat increase your braking leverage, but the pad-dive angle will be worse unless the rim width is increased.
Some of those Trek touring bikes had rather poor vertical clearance atop the front tire, and 700c rims will allow a considerably-wider tire to be fitted.

RRJohn

ddd,
Thanks for the information on the rims, chain and your change to the hub. Is there a particular Shimano 6 or 7 hub that works best for the retrofit?
Robert

sunnyone

https://www.bikeforums.net/classic-v...5-shipped.html

Did you see this thread about a great deal on some really nice 27 inch wheels?

gmvelo

I've got an '85 620. Lovely riding bike. When fully loaded including low-riders up front it really shines.

When I picked it up, it had a low quality rear wheel (StaTru) and the original front, both 27". The first thing I did was switch over to some 700c wheels I had sitting around. It just barely works with the brake reach of the canti's given the post location, but I've never looked back. There is so much selection when it comes to 700c tires. If I were buying a new wheelset, after confirming that 700c will in fact work with the brakes (as suggested by ryansu below), I would definitely make the switch. As an added benefit, you also get a bit more tire clearance.

ryansu

that deal evaporated quickly...

RRJohn

Thanks for the heads up on the link. Seems like a very good deal for a set of wheels.

cannonride15

If you're more a 'ride it as is guy' then why do you want to swap out the Helicomatics? If the cups and cones are in good shape then merely rebuild same. Even if cones are shot I've found replacements.
If you need to swap out freewheels for different terrains then that might be an issue unless you have several Helico freewheels.

RRJohn

That’s the plan but I won’t know the hub/cone condition until I get it apart and could’t help myself from thinking ahead. Best case is all works properly and I can load up and go.

The Golden Boy 

I have a 1985 Trek 620 and an 85 Trek 720. They're both very similar bikes, designed by the same people, adhering to the same concept, built to similar geometries, with similar materials and similar spacing- as they were both designed in the same year, by the same people to the "standards" that were in effect at that time.

Up until a few years ago, I ran both with 27" wheels. I don't trust the Helicomatic hubs for anything. Sure, there's plenty of anecdotal stories of Helicomatics working fine 40 years down the road- however there's more than enough anecdotal evidence to support the reasons for swapping out Helicomatic hubs.

I have scored a few decent sets of wheels- and really, you can get some REALLY sweet 27" wheels for under $100. For around 8 years or so, I ran with the 27" wheels- and really thought there was no reason to change them out. Paselas are great tires, and the Sand Canyons are great tires. Aside from a set of cheap tires, I haven't used any other of the 27" alternatives.

At this very minute- my Trek 620 is wearing a set of 36 spoke Avocet sealed bearing hubs laced to Super Champion Modele 58 rims with Sand Canyon 1 3/8" tires. They're excellent wheels, and exceptionally beautiful wheels- IIRC- those cost me $60 on eBay- but the shipping was crazy expensive. Unless you get a good deal on the shipping- I wouldn't suggest going that route. (I also have a set of 40 spoke Phil Wood/Super Champion Modele 58 wheels that I occasionally use on this bike)

The primary reason to keep using 27" wheels is that 80s tourers were designed around 27" wheels. Not only that, but because they were just figuring this sort of thing out- the spacing of the canti bosses (especially on the fork) is much narrower than bikes made even 5 years later. This greatly affects what brakes you need to use.

A couple of years ago, I switched my Trek 720 over to 700c wheels. Because the bikes were designed around 27" wheels, I was kind of hesitant to do it- but after looking at a WHOLE lot of pix, I realized, with the right brakes, these bikes would be fine with 700c wheels. I'm really, really glad I did it. My 720 is wearing a set of 36 spoke 10 speed Phil Wood/Velocity Atlas wheelset and I'm running 35cm Compass Bon Jon Pass tires. Some people "don't believe the hype" about Compass tires, supple tires at really low pressures... I would be skeptical of the opinion of anyone who yaps about Compass/supple/low pressure tires being all about marketing or 'sheeple' or 'hobbit people' or whatever.

I do not believe there's any real practical, discernible difference between 27" and 700c wheels. The difference is going to be whether the brakes/braze ons reach the rims at a decent angle and what tires you can use. The colossal reason for swapping to 700c is the availability of tires and the ability to use tires wider than 32/35mm (1 1/4" or 1 3/8"). After my experience with running 700c wheels on my 720- the only reason I'm using any 27" wheels is because I have them and because of the cost involved in swapping over to 700c wheels.

I currently am having a set of 700c wheels built for my 620- a 32 spoke 10 speed Phil Wood rear and SON front laced to Pacenti Brevet 700c rims. I will be using Compass Bon Jon Pass tires on it.

For your 620- if you were to swap over to 700c wheels (or even to change to different 27" wheels), I would strongly suggest to keep the Maillard/Spidel skewers that came on that bike- those things are great- they tighten and release easily and securely- and they'll work even if you run a 130 rear end on there. I would also strongly suggest that you keep the original BR MC-70 brakes or if you upgrade- the XT M732 cantilevers. A lot of the older 80s cantilevers will have the adjustability to work with those frames and the height they have to work at. Plus they're really attractive. Some of the newer cantis may look pretty slick- and may have cool features or less weight or appear to be more burly, or come with buckets of recommendations- the point is again that the 80s tourers generally have a much closer spacing than those brakes were designed around. Another of the big plusses about the 1985 Trek 620 is that they were spaced at 128- so you could use a 126 or 130 spaced wheel without any trouble- and the outrageously long chainstays (aside from contributing to the 1972 Cadillac Eldorado class ride) also give you an option to go wider if you so desire.

Good luck- and post some pix!!!


1985 Trek 620 by Dave The Golden Boy, on Flickr


1985 Trek 620 by Dave The Golden Boy, on Flickr


1985 Trek 620 by Dave The Golden Boy, on Flickr


1985 Trek 620 by Dave The Golden Boy, on Flickr




And here's a couple pix of my 720 with the 700c wheels- so you can see the angle of the pads in comparison to the 27s above (I'm using early 90s Suntour XC Pro brakes- only as a stylistic choice- not because of necessity)


IMG_0551 by Dave The Golden Boy, on Flickr


IMG_0616 by Dave The Golden Boy, on Flickr


IMG_2377 by Dave The Golden Boy, on Flickr

RRJohn

Dave,

Thanks for the extended reply. The original 27” wheels need some work but should be fine . We’ll see about the Helicomatic. Here is the CL photo that hooked me.

RRJohn

Here are a couple of more photos of the current condition. Fortunately, it was kept inside the shed. Lots of work ahead!

pastorbobnlnh 

Just an FYI: I recently serviced my first Helico Matic freewheel. I'm all set with the needed tools to do so. If your Helico freewheel shows little wear, you can continue to use the current wheels.

tyler_fred

RRJohn,
Bruce was ready to cut a deal on that 620. He asked me to make an offer, but alas, I couldn't get to Raymond in time. Kudos to you.
What is the stand over height? Hopefully you'll say "Too small for Tyler_Fred". That would ease my grief over a missed opportunity.

jlaw

It's interesting that a bike can sit in someone's shed for 20 years and look pretty pathetic, but that green 531 Reynolds decal still glows! Draws me right in.

@RRJohn, what is your plan for this rig? Are you going to take it down to the frame and re-furbish?

RRJohn

Tyler Fred-I was surprised no one had snapped it up, maybe the condition was to much work for most folks. I'm sure it is too small of a frame for you!

Jlaw- Yes, I will take it down and replace whatever is needed and then load it up and ride. My current bike is a 1985 Fuji Series IV that is best riding bike ever, so it will be interesting to see how this one compares. Hope to start next week on the rehab and looking forward to getting into the Helicomatic hub.

tcpasley

FYI - Here is a trove of Helicomatic cogs, spacers, and freewheel bodies available in my neck of the woods:
Helicomatic gear cogs and free hubs made by Maillard - $50 (N. Raleigh) => https://raleigh.craigslist.org/bop/d...868973629.html

Not sure if the seller would ship, but the deal looks good.

jlaw

@RRJohn, you're going to need the freewheel tool shown below or an improvised tool if you want to remove the Helicomatic freewheel.

If you don't have this already you might find one on ebay or perhaps your local bike shop. Maybe someone on this site will let you borrow it.


Also, re: new brake pads - Kool Stop pads will work with the brakes you have. If you buy the Eagle 2 model (internal backbone) you may have to trim the length for the front to get them to not hit the forks. They will probably work on the rear as is. Some on this site have used one of the Kool Stop road-style pads that have a 'holder' with replaceable pads - and they didn't hit the front fork because the entire mechanism is shorter than the Eagle 2's. Investigate before you buy.

Kool Stop International - High Performance Bicycle Brake Pads Since 1977

I put the non-threaded Kool Stops Eagle 2's (black and salmon) on my Trek 620 and they stop well - I get a little squealing if I ride them hard for a distance,but nothing major.

jlaw

@RRJohn

Also, if you want to disassemble the Duo Par rear derailleur there is a Youtube video by 'RJ the Bike Guy' showing his experience doing this. I took my Duo Par completely apart and cleaned/rebuilt, but when I re-assembled I somehow caused the cage to bind in certain positions - still haven't solved that one - and my Duo Par had a couple more pieces than the one shown in the video.

I wound up putting a spare Shimano RD on the bike because I also installed a 7 speed which, it appeared to me, the 6 speed Duo Par could not handle.

Duo Pars can handle a fairly large cog (32T +) and were evolutionary in their day, but they are known to be a bit fragile.




There's somebody on ebay who wants $219 for the one shown in this photo!

The Golden Boy 

I would not bother ****ing around with the Helicomatic. There's literally dozens, if not hundreds, if not thousands of other hubs out there that don't have the propensity for breaking spokes or blowing up the tiny bearings or having soft races like the lower level Maillard Helicomatics irrefutably have.

I would also not **** around with the Duopar. Again, there are literally dozens, if not hundreds, if not thousands of other derailleurs that don't present the issues that these have. If you want to stay period correct, or vaguely period correct, there are many excellent, top quality long cage derailleurs available that have the same range as the Duopar- with none of the dual parallelogram, triple pivot issues.

Yes, the Duopar was revolutionary- it was the outrageously expensive gold standard of the time- it could handle a 38T cog. There are many people that have used them for decades without issue. It could shift unbelievably smoothly. It was also made from stamped steel and plastic with cheap pulleys. IMO/IME a Suntour XC triple pulley RD has the same capabilities and none of the inherent issues or cheapness that a Duopar Eco have. Step up to a Shimano M730 or M735 XT derailleur or a Suntour XC Pro or XC Comp and you have an incredibly "better" derailleur.






I personally think if you have a bike as nice as an 85 620, with XT brakes- spend the extra bank on the Kool Stop Cross Pads, with the fancy shoes, so they don't look like cut off MTB pads.


Kool Stop Cross Pads by Dave The Golden Boy, on Flickr


XT XTR1 by Dave The Golden Boy, on Flickr