Altair 4

So my brother-in-law finds bikes at garage sales and picked up a Cannondale Black Lightning in fair shape. Frame is a little rough at the left chainstay along with a few scratches here and there, but it appears to be structurally sound. This is the first bike I plan to disassemble, clean, lube and rebuild myself. Other than missing the right pedal dustcap, it looks pretty complete and complete, based on what I see in an online vintage Cannondale catalog. Some strange stuff on on-board, including Ovaltech chain gears.

The bike has the SunTour Accushift levers on the downtube with a SunTour Edge rear derailleur. The rear lever is marked "friction" and "index." I haven't ridden the bike yet, but on the repair stand, I'm not sure how it's supposed to function in "index" mode. Anyone familiar with how this is supposed to work? To me, after just a cursory look, seems to function the same regardless of where the indicator is pointed.

Thanks for any insights you can spare on this extinct system!

bradtx

Altair 4, Basically in index mode there will be a detent for each gear which friction mode won't have. Try switching index/friction when the lever is at full forward position.

Brad

OldsCOOL

It probably isnt a true Black Lightning. The bikes didnt come with accushift that year. Ok, index feature and friction....unsnug the black tightener and then twist the outer bezel until the indicator lines up with "friction" or "index". See if that helps.

I have a bike with accushift.

John E

I have the Accushift thumb shifter on my mountain bike. The first thing I did was to change it to friction mode (and leave it there), which made my subsequent conversion from a 7-speed freewheel to an 8-speed cassette pretty painless. As others noted, it should click at each gear if the index mode is working properly, but I can assure you it is no great loss if it does not.

Bianchigirll 

It isn't much different that shimano' index shifting.

oldbikenewbike

Photos?........

Velocivixen

Not exactly sure what you're asking. As other mentioned you alternate between friction and Index settings by loosening the center nut on right shift lever and turn the dial so the mark lines up with either Friction or Index, the retighten bolt. Index means that for each shift you will hear/feel a "click"; friction is like driving a manual transmission - you find the gear. No clicks or predetermined amount of cable pull.

please post photos of the drive train side, up close. Thanks.

Altair 4

I'll try that.

This catalog https://www.vintagecannondale.com/year/1989/1989.pdf , page 22, disagrees with your thought that it isn't a true Black Lightning. Every component matches up to what is on this bike. I'll check out the bezel and indicator lines.


Thanks, John. I'm not worried if it doesn't work (or work well), I'm just really curious about the development of indexed shifting. The next newer bike I have (the Trek) has the Shimano trigger shifters while the oldest bike I have is strictly friction shifting. So far, I'd put this example in the "almost works" category.

Soon.

Altair 4

I'll post up some photos as soon as I get a chance to work on it a bit, including your requested examples. Work and offspring commitments taking precedence right now. Thanks for the explanation.

RoadGuy

I just removed the Surtour Edge 7-speed shifters and derailleurs from my Trek 1100 if you need parts. They work fine, but I was changing the wheels and upgraded to a 8-speed cassette with Shimano derailleurs and downtube shifters.

The Suntour Accushift differs from Shimano index shifting in that the distance traveled by the rear derailleur between cogs diffs on one end of the freewheel to the other. On Shimano index systems the cogs are spaced equally from one end of the freewheel (or cassette) to the other. For this reason, freewheels designed to be used with a Suntour Accushift system are different from standard freewheels used with friction shifting systems and from freewheels used with Shimano index shifting systems.

I read that the Suntour Accushift shifters and derailleurs were/are not compatible with Shimano Index shifting components, and I was curious to test this myself.

Most 6 and 7 speed downtube index shifters have a selector so you can switch from index to friction shifting for the rear derailleur. This was useful when riding if the index shifting stopped working correctly, the rider could switch to friction shifting. While there are 8, 9, and 10 speed downtube shifters available from Shimano, it appears that the friction/index option has been deleted from them, and while the front shifter is friction only, the rear shifters are strictly index now.

So, when I was in the process of switching from Suntour to Shimano (still using the Suntour/Sakae Edge triple crankset), I tried some combinations of parts, just to see if they would work. The Suntour Edge rear 7-speed derailleur does not travel far enough to hit all 8 gears of a Shimano 8-speed cassette. I was able to get the Suntour Edge downtube shifters and derailleurs to work good with a Shimano 7-speed cassette and a spacer on a new 8/9 freehub rear wheel, AND a 8-speed cassette with the limit screws set to cogs 2-8, locking out the low gear (largest cog). I switched to Shimano 105 9-speed front and rear derailleurs and the Suntour shifters and was able to get the same 7-gears sucessfully on the 8-speed cassette. Then switched to Shimano SL-R400 8-speed downtube shifters and readjusted the limit screws on the rear derailleur to get all 8 cogs.

My next planned change is replacing the Suntour/Dia Compe Edge single pivot sidepull brake calipers with the more modern/stronger Shimano dual pivot sidepull brake calipers and Shimano aero brake levers.

OldsCOOL

Is it a criterium series frame? Great bike, regardless and an excellent pick up.

The Golden Boy 

I've had flawless performance of Accushift 6 speed components (shifters and derailleur) with Shimano 6 speed freewheels. I have that combination running on two bikes. I have Accushift Shifters and derailleurs on an IRD 5 speed freewheel; again, it works flawlessly.

No Fault Shift Assurance: Accushift.

Altair 4

Yes, 3.0 series, with the funky cantilevered rear dropouts.

1991BRB1

+1 to add that Accushift works and it's more versatile than what you sometimes hear.

I understand the initial rollout of the Accushift system was plagued by lack of consistency between freewheel teeth, chains, cables, etc. when shops or OEM Spec'-ers would not spec the recommended parts and attempted to swap or skimp on some components. These were the days before the idea of a complete component group really existed. Shimano SIS got a reputation for working better than Suntour Accushift but this was in part because they reinforced the uniformity of all components.

But I digress. I run 7 speed Accushift Plus in index mode and I like the very positive and satisfying "chunk" of the shifting mechanism. I don't have a NOS Suntour Superbe Accushift Chain (rare and dear if you do find one) but I've had tremendous success with a modern 8 or 9 speed chain. I actually think this makes a positive difference in the shifting performance. I also use Campagnolo "compressionless" cable. I use a Winner Pro/New Winner 7 speed freewheel and the 7 speed FW's are the only ones, I believe, that have varied spacing between the cogs ( 5 mm outer cogs and 4.8 mm inner cogs if memory serves). I think, and the quote above would affirm, that the Suntour 5 and 6 speed (non Ultra) spacing is the same as most other brands.

I've often wondered if it would be worthwhile to "fake" a Suntour 7 speed cassette using Hyperglide cogs and swapping in spacers to obtain the Suntour setup.

I would recommend downloading the Suntour Accushift Technical Bulletin 21. It's available in .pdf form on one or more Suntour enthusiast sites. Good insight about what works and how to set up the system, as issued to bike shops.

OldsCOOL

We Cannondale Crit lovers are quirky like that.

OldsCOOL

Mine has been flawless as well. When properly set up it wont miss a single shift and I have the more base level A-4030.

oldbikenewbike

Here's the Catalog page....

cbender

I've also had no trouble with the Accushift on my Bridgestone. I'm running the GPX group, with a alpha 7 speed freewheel. I adjusted the RD setscrews per the instructions in the Suntour technical manual (Suntour Technical Bulletin #21 "Accushift Problem Solving" in 31 Pages) and have had no problems since. The shifting clunk is comfortable, and I very much like the ability to shift several cogs in one go.

The Golden Boy 

Forum member @mrmw did that and made some nice instructions:

https://www.bikeforums.net/classic-vi...r-15-hawk.html

1991BRB1

Super helpful. That's exactly what I was getting at. Thanks

Altair 4

Thanks to everyone for the instructions on setting the Accushift for the rear derailleur. Works like a charm although the volume of the sound of the shift was a little startling. I took a couple of photos this morning, but they're pretty bad - poor lighting in the basement and, at 14 degrees here this AM, too cold to drag the bike outside for a photo session. Nonetheless, here are a few closeups:


Rear Derailleur


Wolber Rim Label


Seat Tube Label


Right Pedal (MKS AR-2 in black) with missing dust cap


Ovaltech Chain Rings


Rear Derailleur Shifter with Accushift Indicator

Serial number shows it is a 58 cm frame size, built in early March, 1989 with a sequence number of #58 . Would that be the 58th bike that day, month, or year?

The bike is really dusty and even "furry" in places. It's been setting a long time since it last was ridden. As far as I can tell, everything is original including the chain and tires. The rear tire is showing some wear but the front looks really good. The paint on this thing is really fragile and whoever owned it certainly didn't baby it.

I'm going to check out a few LBS that specialize in vintage bikes here in Pittsburgh and see if I can source a replacement dustcap in black. After noting that the right one was missing, I checked the left one and found that it was very loose. Is there a special tool to torque these?

Altair 4

So I've made some progress on this bike. I cleaned and lubed the pedals and replaced the missing dust caps with parts from Niagara Cycle. The headset was a mess of dried out grease and had developed a notchy feel in the "straight ahead" position. I had it replaced it with a new black Origin8 unit that restored a nice smooth feel. The bottom bracket has been pulled and the threads lubed. Wheels are trued. I've cleaned all of the dust "fur" off and it's starting to look pretty nice. Shifts work great in friction mode, but in Index mode the chain wants to ride up on "top" of the gear teeth on the freewheel, not fully seated. This happens on a few different gears, but not all of them. Other than that, I think it's ready ride (other than the fact that it's going to be brutally cold here - high of 6 degrees on Sunday?!?!).

Is there a trick to changing from friction to freewheel, in the sense of should the chain be on the large or small sprocket when changing from friction to index?

Bianchigirll 

It doesn't ma where the chain is when you change from index to friction. The friction setting on early index shifters was for use if the system got out of adjustment on the road, perhaps a minor crash or something.

You do need to be sure the bike is correctly adjusted for index shifting. Suntour was a bit more finicky that shipmano but once set up correctly it should work fine.

OldsCOOL

My Technium has the accushift 3040 and took some tweaking when it did the same as yours. When in index mode flip the shifter all the way forward. If there is slack in the cable you may have to loosen the cable clamp at the derailleur to pull it tight. When you do, be sure the barrel adj is set halfway. Next cut a fresh 12" length of cable housing to help free up any stickiness. Somewhere in this process you should spray the inside of the derailleur with a cleaner/lube to remove any stickiness there as well. Next, it's ready for tension on that shifter to see if it hits every gear. You may have to adj the barrel here or there.

Chuckk

Here's the Suntour page on the '88 Accushift

RE - P - UL = (5&6) - Friction - 7
My Lightning came with a 7, and was set to RE = poor shifting.

Accushift must have been developed with a specification for a LOUD click, makes people look and wonder.