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Discussion Starter · #1 ·
I've just put a set of '06 Boxxer Ride's on the Pack :D , and have found the instances of chain drop & annoying chain slap have increased to the point I had to have a dual ring device.
Being in Australia, any dual ring guide bought locally costs between $200 & $320, so after reading through cheezy's thread on chain guides, I figured it couldn't be too difficult to make my own. (after all, you guys have done all the hard work of trial and error :thumbsup: )

I decided to take cheezy's advice that the best combination was a Heim 3-guide coupled with an MRP LRP roller, this also looked the simplest to copy.
Using the photos from the thread and Heim website, I scaled them and made a cardboard template that I then transfered to some 1.5mm stainless sheet.
(I found a local stainless sheet-metal fabricator that had no problems letting me sort through his scrap bin for a few off-cuts.)

I was previously running a 2.5mm spacer on the drive side with my Hollowtech cranks, so I also grabbed a sheet of 1mm, to make another spacer so the chainline would be uneffected.

The only tools required are: 35mm holesaw, sharp 6mm drill bit, jigsaw with appropriate blade for stainless and a file. (a bench sander/grinder also helps)

Once I had the guide cut out, I went back to the stainless fabricator armed with a 1/2 dozen beers and he folded the 90' bend for stiffening on the bottom edge.

I also decided to use one ISCG mount to make sure the guide could never move. This meant I had to grind down the head of a 6mm stainless bolt to approx. 1mm thickness so it would clear the inside face of the granny ring bolts.
So in order of assembly: 1.5mm stainless guide plate + 1mm stainless spacer + external BB bearing. This leaves about 1mm clearance between the iscg bolt and granny.

The only cost, apart from a few hours labour (and the beers), was the LRP roller ($35 aud)

Once all together, it worked like a charm from first revolution. Couldn't be happier, no more chain drop, suck or slap.

Its worth having a go at making your own, if you're thinking about a guide......not hard & ridiculously affordable.
Thanks to tscheezy for your guide thread
cheers
leight

Here's a few pics
 

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Natl. Champ DH Poser/Hack
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well im impressed as hell, L. after followin cheeseball down his road myself, i gotta ask why ya chose to anchor the plate? im sure ya read all the same stuff i did. maybe ya have a new thought on why this should be done that the rest of us havent thought of. very nice work man.
 

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Looks Good

Another good call is the Blackspire Stinger dual ring chain tensioner. I just got one for my RFX/6Pack with the ISCG mounts. Easy to install, easy to set up, and very inexpensive (~$30). This guide along with your favorite chain guide (~$25-$35) gives an inexpensive, easy to use, very reliable setup.

Enjoy!
TG
 

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Discussion Starter · #5 · (Edited)
cactuscorn said:
well im impressed as hell, L. after followin cheeseball down his road myself, i gotta ask why ya chose to anchor the plate? im sure ya read all the same stuff i did. maybe ya have a new thought on why this should be done that the rest of us havent thought of. very nice work man.
Probably me just being a bit anal really, but I noticed there is a slight gap (1mm) between the face of the BB shell and the ISCG plane. I noticed on trial fittings that I could flex the guide laterally, so I sandwiched a 1mm stainless washer between the guide and the iscg mount to fill this gap. This stiffened things up noticeably. I think the flex is due to the 90' bent edge of the guide not extending far enough onto the ring (see pic) (my design flaw)
But with one iscg mount, it's as solid as a rock.

I also found that when just relying on a sandwich-mount fit, I could make the guide move up and hit the chainstay, with a sharp hit. I didn't want this to happen if it took a hit from a log/rock. I'm still having second thoughts as to if this is wise or not.
(Now any load from a hit will be transferred into the iscg tab or try and bend the guide. I think I know which one will give first)
 

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Hey, G-AIR! I was looking at the Stinger recently for my 2005 Six Pack as well b/c I couldn't get my ISCG mounted MRP LRP to get along with my granny ring b/c it was just way too thick. The chain would rub on the chain tensioner plate in the granny ring and my cranks weren't securely over the spindle. How thick is the ISCG stinger where it mounts to the ISCG tabs? What type of bottom bracket and cranks are you using and what year RFX/6Pack? I'm looking for a cheaper alternative to the TSCheez heim arm/MRP roller combo w/o having to do a lot of modification. I'm no do-it-yourself kind of guy. Thanks!

G-AIR said:
Another good call is the Blackspire Stinger dual ring chain tensioner. I just got one for my RFX/6Pack with the ISCG mounts. Easy to install, easy to set up, and very inexpensive (~$30). This guide along with your favorite chain guide (~$25-$35) gives an inexpensive, easy to use, very reliable setup.

Enjoy!
TG
 

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Natl. Champ DH Poser/Hack
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yeppers. exactly the things i was considerin when i mounted mine. i almost went the same direction you did but cheese talked me out of it for the same reason you bring up. still, yer work looks great. be proud.
 

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Leight said:
Probably me just being a bit anal really, but I noticed there is a slight gap (1mm) between the face of the BB shell and the ISCG plane.
Nice work Leight! On your next one why not increase both the inside and the outside diameter so that it doesn’t interface with the BB at all, and just bolt the sucker onto the ISCG tabs? I've made the move from a Heim to a Blackspire Stinger because I think it's better to keep the systems independent. Never had a problem with the Heim, but all the same I think it's a little cleaner.
 

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Why's the FD so damn high from the rings? I thought that since you've removed the big chainring you should put the FD lower, near to the crank. :confused:
 

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Hey Oreo the tolerances are extremely tight when trying to use a Stinger with a 6 Pack's ISCG tabs, and you ought to verify a couple of things before you order one.

Are your ISCG tabs parallel with the face of the BB shell? If not it your tabs will push the Stingers plate into the small chain ring bolts.

How much further do the ISCG tabs sit back from the BB shell? You'll need at least 1mm preferably more depending on which cranks you use (see next question). Mine had 1mm.

Which cranks are you running? I couldn't get the Stinger to work with my RF Atlas cranks, but it would with my XT. I guess if you had more clearance between the face of the tabs and the BB shell face you could use the RF cranks.

To make mine clear I also had to file all of the excess material, paint and burs, off of the ISCG tabs, similar to facing the BB shell, and I didn't install the washers behind the plate that Blackspire supplied. This also required that I run down to Home Depot and purchase some additional pan head bolts that had threads cut all the way down to the base of the head. With all of that I was able to get 1mm of clearance between the face of the Stinger arm and the bolts of the small chain ring.
 

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pecka said:
Why's the FD so damn high from the rings? I thought that since you've removed the big chainring you should put the FD lower, near to the crank. :confused:
Nope. If you lower the FD much from the 3 chain ring position the chain stays will smack the bottom of the FD cage under full compression.
 

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Hey tscheezy and CC, I want to use your setup for the Utah trip, could you guys tell me exactly what I need and I will have Larry order it for me. CC- I also want to go with a wider BB so I can run a 2.5 in the back if I want, was that a 118 BB for the 952's? I might need your expertise too for installing it correctly. Thanks!

Sorry for the slight derail Leight, very nice work!

**edit: Crash is taking care of me with a heim guide so I will just order the LRP roller and BB, thats it I think, CC- if you could confirm the BB size, thanks!
 

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CrashTheDOG said:
Hey Oreo the tolerances are extremely tight when trying to use a Stinger with a 6 Pack's ISCG tabs, and you ought to verify a couple of things before you order one.

Are your ISCG tabs parallel with the face of the BB shell? If not it your tabs will push the Stingers plate into the small chain ring bolts.

How much further do the ISCG tabs sit back from the BB shell? You'll need at least 1mm preferably more depending on which cranks you use (see next question). Mine had 1mm.

Which cranks are you running? I couldn't get the Stinger to work with my RF Atlas cranks, but it would with my XT. I guess if you had more clearance between the face of the tabs and the BB shell face you could use the RF cranks.

To make mine clear I also had to file all of the excess material, paint and burs, off of the ISCG tabs, similar to facing the BB shell, and I didn't install the washers behind the plate that Blackspire supplied. This also required that I run down to Home Depot and purchase some additional pan head bolts that had threads cut all the way down to the base of the head. With all of that I was able to get 1mm of clearance between the face of the Stinger arm and the bolts of the small chain ring.
Crash. Thanks for the useful information. Glad to hear that you got your Stinger to work.

I only have 1mm between the BB shell. However, I'm not sure exactly what you mean by how much further do the ISCG tabs sit back from the BB shell. Aren't they usually flush with the BB shell? I also only have one set of cranks and wouldn't you know it---they'd be RF Atlas too.

TSCheezy's method is looking pretty good right now and I think rroeder is asking for the instructions too.

Sorry to digress, Leight! Awesome work!:thumbsup:
 

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Discussion Starter · #14 · (Edited)
Don't be sorry guys

keep the info rolling....

Oreo - on my Pack (and it seems others are the same) if you were to put a strait edge across the BB shell face so that it crosses one of the iscg tabs, you should find that the tabs are actually set back in about 1mm.
This is the gap I filled with a 1mm washer to help stiffen up my guide when sandwich mounting.


Crash - In hindsight, I probably would have opted for iscg mounting, had I realised prior to cutting out the guide that I could definitely use the iscg tabs with very low profile mounting bolts.
However you bring up another good point about the tabs needing to be parallel with the BB face. In my 4th pic (the one looking down on the guide) you can actually see that the iscg tab is bent in slightly. This happened after the chain dropped to the inside (pre-guide days) and I tried to pedal it out as per normal. Somehow it all jammed up and resulted in a bent iscg tab. That would have to be straightened before iscg mounting would be an option now.
 

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NIce work Leight. I am running the same crank/BB Setup as you on my pack, and I am using the Blackspire Stinger. I am using only one 2.5 mm spacer on the drive side, and everything fit perfectly, with no clearance issues. The Stinger only costs $30.00 USD. I highly recommend this over the heim if you are running the new XT cranks.
 

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MBN said:
That's a good deal on the heim, but you will want to get an LRP roller to replace the Heim roller. The Heim roller(at least on the version I had) had an issue with back pedaling, the chain would drop into the little ring every time. You might as well go with the Blackspire Stinger, and save yourself a bundle, and you don't have to sandwich it between the shell and cup.
 

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El Chi- aside from the price, what do you think makes the Stinger better than the Heim (w/ LRP roller)? Stiffness? Material?
 

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tscheezy said:
El Chi- aside from the price, what do you think makes the Stinger better than the Heim (w/ LRP roller)? Stiffness? Material?
The fact that you don't have to sandwich it between the BB and Shell for one, and they are a bit stiffer as well. Another thing that makes it more appealing is that it is easy to make small adjustments too. And it's cheaper.
 
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