Rode with a guy using one of these rather tempted to get one but not sure if they’re worth 150euros, anyone have any experience of them?cheers

No, but i have just ordered one of these from the states;
http://forwardcomponents.blogspot.com/2008/12/eccentric-bottom-bracket-patent.html
Same thing, but works out a bit cheaper due to exchange rates, however, the first one i ordered 8 weeks ago got lost in transit & i’m still waiting for the replacement. So i’m not yet in a position to comment.

There are a lot of positive comments about both over on the forums at mtbr.com

The Forward Components eccentric external BB works the sam way as the (earlier designed) Trickstuff Excentriker which I am using on my Singular Pegasus prototype.

My observations to date, based on the Trickstuff one:
– they work reasonably well, but you may need to use a half link to get your chain tension right, as they don’t have a lot of ‘throw’
– they are expensive – €149 for the Trickstuff – but produced in relatively small volumes with a lot of development so that’s understandable
– they are a very ‘tidy’ solution and are largely ‘invisible’ once installed (compared to a regular EBB)
– because each side is adjusted independently, it is relatively easy to set the cups slightly ‘off’ which will put additional load on the bearings
– they can be difficult to adjust once covered in mud (Forward Components may be easier due to the scalloping which could give more purchase)
– you cannot use most HTII chainsets on these BBs without taking a grinder to them. Triple chainsets will need the granny ring mounts filed off, while if you are a fan of converted M960 XTR chainsets they won’t fit at all due to the edge of the spider curving inwards (usually over the BB cups, but these are much larger to allow for the eccentricity)
– the plastic top hats on the Trickstuff model are very fragile and brittle
– I don’t know how readily available replacement bearings are for the Trickstuff model, should be fine for the Forward Components model which uses standard Enduro bearings
– the chromed finish on the parts of the Exzentriker that you screw into the BB is rubbish. The Forward Components looks much better in this regard
– a specific tool is needed to install the Trickstuff model which is not included with the BB (an extra €15), Forward Components are including a tool with theirs

Given the choice, I’d rather have a proper EBB (apparently Phil Wood are working on a ‘half length’ EBB which would reduce the issues regarding crank-saddle alignment), but these are a viable solution and are much easier to use than a dropout mounted tensioner. They also look a lot better.

If you have a frame that you want to convert to SS use and are prepared to pay a significant premium over the cost of a dropout mounted chain tensioner, I’d get the Forward Components over the Trickstuff model.

Nice products both but as AdamM points out they are independently adjusted I cannot imagine the bearing life being that great, especially considering the extra load of SS pedalling. I’ve though about getting one often but always end up going back to a Surly Singlator as a cheaper option that does not require fettling or replacing my cranks.

awesome reply AdamM many thanks i’ll take your advise on board

No worries. Feel free to email me if you have any other questions.

OEMs usually specify and purchase cartrdige bearings from a catalogue of standard sizes. Look for the code on the seal, 6805 on the ones from my Excentriker. Don’t know the original manufacturer but as that’s a standard size you could use an SKF double sealed 6805 2RS1, for example.

My experiences with an Excentriker
It is fiddly to align the two halves. Not least because as you tighten the cups they slip (due to tightening on a taper).

Then when I loosen the screws to adjust, I find the cups are locked, due to the taper. So I need to tap gently on the “nuts” with a screwdriver and hammer. Not as bad as it sounds once you have the routine sorted, but add in mud and you get the idea.

I have also dimpled the surfaces by tightening down hard, which could limit positions for future adjustment. Am I tightening it too much? Probably, but I found the cups slipped if not locked down tight. They haven’t slipped since.

FWIW
I made my own tool to tighten the cups in the BB, from a piece of srap metal and two screws.
I have used 34:16 and 34:17 without a half link
I cut the inner lugs from a deore HTII crank with a junior hacksaw and a small file – no scuffs or damage if you take your time and have something to hold the cranks steady.

mos – Member

No, but i have just ordered one of these from the states;
http://forwardcomponents.blogspot.com/2008/12/eccentric-bottom-bracket-patent.html
Same thing, but works out a bit cheaper due to exchange rates, however, the first one i ordered 8 weeks ago got lost in transit & i’m still waiting for the replacement. So i’m not yet in a position to comment.
mos – I got mucked about a bit by Forward Components and ended up cancelling my order for one of theirs around Christmas time – supplier problems, they said, but they came up with a number of excuses for not shipping. He did refund my PayPal promptly when asked, so I’m hoping you’ll be ok even if it doesn’t turn up. It did look the better bet when compared with the Excentriker, but I have to say, I gave in in the end and bought a horizontal dropout frame, as the prospect of £150 or thereabouts on one of these two was a bit too much to take.

My way around the granny ring tab problem was to simply go for a 34T inner ring on a roadie compact chainset, rather than grinding away a triple.

Adam’s pretty much got it covered, my experience very much accords with his. I’d only add that their bearings are pretty shonky, though this isn’t helped by the possibility to misalign cups. In short, they are a really nice idea but slightly poorly executed with regard to materials. A ‘mark II’ version could be fantastic.

My way around the granny ring tab problem was to simply go for a 34T inner ring on a roadie compact chainset, rather than grinding away a triple.

Which is exactly what I’ve done as well, although not all MTB frames will have sufficient clearance to the chainstays for this to work.

Like my Inbred, for example. Hence the £15 outlay for the Deore HTII chainset – bought one new and sold the rings straight on.