gnawd87

Hi everyone,
I recently purchased a old 1982 trek 614.
I want to eventually convert from its current drivetrain ( 6 speed downtube friction) to an 8 speed indexed bar end setup. However, funds are somewhat short right now, so i cant do it all at once.
I got some new wheels for the bike last week (a set of 700c sun cr18 w/ sora hubs) and was thinking now is a good time to do the 8 speed upgrade.
My question is, can i simply put a 8 speed cassette on the new wheel and get a new chain and run everything in friction until i have time and money for the other parts? is the rear derailleur (suntour cyclone mkII) capable of shifting 8 gears or do i need to buy a RD capable of 8 or more gears?


Thanks in advance for your help,
D

RobbieTunes

Well, I'm not sure if the Cyclone MkII will go the extra 4mm, but it's worth a try. Open up the adjustment screws and try it. Everything else will work, you just may not be able to run all 8 cogs....

gnawd87

cool, thanks robbietunes for the quick reply. ill give it a shot when the new cassette comes in.

Binxsy

You could try spreading the frame, scroll down a bit you will see instructions. You should also read that entire page, very informative.
https://www.sheldonbrown.com/frame-spacing.html

Your LBS may do this for you to, maybe.

I would just say leave it as it is, and maybe go for a 7speed?

Make sure you chain wrap is correct, as long as you cog sizes are correct it should work with 8 speeds.

The maxium cog this RD supports is 26t, and the chain wrap is 28. I am guessing the minimum on this one is 12 or 13.

Bianchigirll 

I would make looking for and buying you Barcons the next priority. even if you stick them on the shelf for bit. better to have them rather then not be able to find them.

gnawd87

Thanks for the input, i already test fitted the wheels by spreading the stays by hand and it wasn't terribly difficult so i think i'm just going to run everything in friction mode like that for now. Maybe when i decide to upgrade everything to indexed shifting, ill get the frame properly spaced and aligned.

The reason why i dont want to upgrade to 7 speed is that im finding 7 speed indexed barcons kind of hard to find. The last used set i saw on ebay went for well over $50.

The bike has a 14-30 6 speed freewheel stock, i guess it was the GT version of the cyclone (more cog capacity?). So im thinking if i stick with something under a 30 tooth cog max, i should be fine. Or what i might do is just buy a new deore or LX RD with higher capacity and not have to worry about it.
Do newer shimano RD's have compatibility issues with suntour downtube shifters in friction mode?


Thanks for the tip. Thats why i wanted to do a 8 spd upgrade vs. the 7 speed upgrade in the first place because i couldnt seem to find 7 speed barcons for a good price. Last time i checked NOS 8 speed shimano barends were still available on ebay but you're right, definitely should get them before they disappear.

Thanks for the replies.
D

jonwvara 

I'm pretty sure I have a pair of lightly used 7-speed Shimano bar end shifters that I'd consider selling or trading. PM me if you're interested.

Homebrew01

"... Do newer shimano RD's have compatibility issues with suntour downtube shifters in friction mode?..."

Most everything is compatible in friction mode. Doesn't mean you can run a 6-speed chain on a 10 speed cassette though.

Binxsy

Ultegra 8sp indexed bar end
https://stlouis.craigslist.org/bik/1528176524.html


suntour ba rend friction 6sp..should work
https://detroit.craigslist.org/wyn/bik/1524629521.html

Binxsy

You might want to find a smaller rear cluster, say a maximum cog size of 28. Might make your shifting easier in higher gears.

roccobike

Don't know how you did with your Cyclone MkII but mine would not travel across the 8 speed hub. It's no big deal, it will handle 7 of the eight gears so you can ride with it. Before you buy the shifters, I'd replace the rear DR with a derailer that is made for index shifting, probably Shimano is your best bet. Then I'd go for the bar cons.

gnawd87

I just got my new cassette this past week; a hyperglide 13-26 8 speed. My Cyclone RD ended up not being able to shift up to the highest cog (26t) also but everything else seems fine. Ill definitely pick up a new RD next, hopefully sometime in the near future.

I'm feeling a little vibration in the pedals when riding and im suspecting its probably coming from the chain (6/7 speed chain) so im going get a 8 speed chain tomorrow and try it out. not really sure where else the vibration is coming from.

One issue i have is when i shift down to the smallest cog (13t) i noticed the chain gets really, really close to the seatstay (<1mm) and was wondering if this is something i should be concerned with. Has anyone else experienced anything like this when upgrading old drivetrain? Will swapping the chain to a 8 speed version remedy this?

Ill try to get a pic of what im talking about.

Thanks for your help.

tmh657

I am not an expert on this but I know what worked for me. I put a modern wheel w/ a 9 speed cassette in a 1985 Trek 660, (w/9 speed chain) and it worked great.

I just looked at a 1986 Trek 560 that I am putting a 9 speed cassette into and just to ride it I used the existing chain that was on the six speed. It is extremely close to the stay so I suspect when I put the narrower chain on there all will be good.

Good luck with your upgrades.

sciencemonster

I used 9 speed chain with a 7 speed freewheel and 8 speed shifters.

8 speed shifters becasue they shift the same distance as 7 speed, and I wanted Ergos.

7 speed freewheel becasue it fit in the back without crowding the stay, I could use my old wheel, and the spacing of the cogs matched 8 speed.

9 speed chain so I had a little extra slop that made the shifting easier and quieter.

oldpedalpusher

I'm really cheap... and went from 6 speed indexed to 8 speed friction shifting on my old Raleigh with no issues. Like you did, I also used wheels with Sora hubs... and a nice little $20 Shimano Sora short cage derailleur works great!





The Sora has larger 11 tooth cogs that can wrap quite a bit of chain without losing tension, even with a little 20t front cog...

sisddwg

The long cage MkII will handle a 34T. I have not experienced any compatibility issues with new Shimano RD's and friction downtube shifters. I use 8spd Ultegra Bar Ends with seven cogs. The L stop screw on the RD adjusted for 7 speed will stop the bar end shifter in friction mode.

gnawd87

I had the impression that a 9 speed chain would be too narrow and likely fall between the chainrings (from vintage-trek website). To those who used 9 speed chains with their setups, did you guys use 9 speed chains because thats what you had laying around? did you have to replace the crankset designed for 9 speed spacing? Are 9 speed chains noticeably smoother and quieter in shifting compared to 8 speed chains? what about chain wear? I was told thinner chains wear out faster but if its not a huge difference and there's noticeable improvement in shift quality it might be something i may consider.

Sorry for all the questions,
Thanks for all your help.

Barrettscv 

You should have no problem installing the wheel without spreading the frame.

tmh657

I didn't have many parts laying around and I got the 660 as a frame set so I cobbled together the complete bike. A 600 crank from a BF member then bought used chain rings locally for it. An Ultegra RD for free. DA 7400 FD from the bay for $11. Shimano 9 speed bar end shifters from ebay.
Then got a smokin deal on a new SRAM cassette and the 9 speed SRAM chain to go with it. On sale at Performance.

From what I have read you MUST use a 9 speed chain to match the width on 9 speed cogs, 10 on 10 etc.
Once the derailleurs were dialed in it shifted perfectly. The cassette was a 12-23 and I have since gone to a 12-26 to get up some nasty hills easier. The close ratio was nice but...

I just popped the wheel in there with a little coaxing and the chain did not have a problem with the stay.

RobbieTunes

Ace