Evening all, decided to take the plunge, bought a chainring and a chainguide on the faithul advice of evans. Took cranks off put new ring on lovely. Put cranks back in, ive got play in the cranks. New bb me thinks. Oh well. Hang on theres no spacers on the bb. Oh that 35£ mrp chainguide is of no use and the one I need is a seat post mount.

How annoying.

So recomend me a seatpost mounted chain guide.

Pauls Components is the prettiest, works as well for a top only guide but can be hard to find in the UK.

Superstar do a seat tube mounted guide but folk say the mount is poor; shame as the BB mounted version is good.

E.13 make a very expensive one, the Audi/Orange 5 boys will say that is best.

73mm shell + truvativ? Reason I ask is that I was able to bodge my way round it by using the LHS truvativ BB cup and a RHS shimano-spec one, which created the space for a spacer/chainguide.

I can’t recommend a seatpost one but both the Superstar post-mounted ones are pretty terrible. The Gusset Lil Chap is the same design. Not completely useless, but they’re too flexible to resist a chain that really wants to come off. (I’ve been very happy with the BB-mount version though)

The MRP 1X is probably good- the BB mount version is the best guide I’ve used. But I’ve not actually used the seat version, and it’s stupidly expensive.

E13 XCX is great, but price does reflect that.

I thought that about the mrp1x, £35 for the bb one but twice that for a plastic one!

Mental.

Any other recommendations?

I’ve got a wierd set up with Rotor Cranks and a ‘Plastic’ frame (that has a different chainline to the seemingly industry standard HT2/Middle ring chainline)so the lateral adjustability of the Superstar was what drew me to it.

The first one bent, the second one bent, I bent it back and fashioned something a little bit stronger using various bits of ‘plastic’ rod…it’s now lighter and stronger and hasn’t bent 🙂

But this is the one I reeeeallly hope santa brings me next christmas 🙂

http://www.xcracer.com/shop/viewproduct.php?productid=279

Seen that but £100 is a lot as well. I have just seen a dmr one that looks so simpe its got to work!

You’d probably have mentioned it if it did, but does your frame have direct mech mounts?

Northwind, unfortunately not, it is a gt 9r so the mech attaches to a little stubby nubbin. No icsg mounts either. Stupid stupid bicycle.

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For northwinds benefit and anyone else who wants to see the stubby nubbin.

Ah yeah, my Idrive was the same.

I’ve got a Superstar seat post mount chainguide and it is indeed a bit rubbish but I modified it by replacing the mounting grub screw and sliding tube assembly with a long bolt and 3 nuts. Now works perfectly. Worth a go for the money.

stubby nubbin

is my quote of the day 😆

Sorry cant be of any help but it made me smile

Right just looked at mine again. Had a thought. As my bb is a gxp 68-73mm or whatever the measurement is could I not use the bb mounted chain guide.

I cant see a reason why I couldnt as I would be extending the bb whichis extendable and the crank axle remains the same whatever.

I wouldnt be affecting a chain line as there is only one ring at the front so no mech to worry about. Correct me if im wrong!

Stayhigh, it was the most descriptive description I could think of. At least I didnt include the colour!

Red stubby nubbin!

You’ll be widening the stance of the bike, which some people care about and others don’t. Not sure if the cranks have enough leeway for that 2.5mm extension, be a bit surprised if they don’t in all honesty but then if it’s truvativ, they do things differently for no reason at all whenever they can.

Did you see up the page about sticking a Shimano BB cup on the chain side?

I did yeah, but would rather try and keep it all one if that makes sense.

How do you mean leeway in the cranks? My view was that I cant buy a set of cranks with a different axle length for a 73mm bb. So in theory I have 5mm before the cranks would be affected if that makes any sense at all?

Yep, cool, just wanted to make sure it wasn’t lost in the noise.

The crank length doesn’t vary when you swap 68 to 73, you space out the BB shell to keep it the same. But what you’re talking about here effectively gives you a 75.5 BB shell- so the LHS arm won’t fit as far onto the splines as usual. Which might or might not be a problem.

Hmmmmm. Extreme but neat solution- do you reckon that there’s actually clearance for a BB mount? The idrive whotsit is aluminium, could it be turned down slightly to reduce your BB shell width?

Assuming the bb is currently 68mm that would make it 70.5mm.

Whatsit? Which bit is that? The actual bb shell or whatever its called?

I was so proud of myself as I was scared of the bb and now im disappointed at my lack of knowledge!

Forget that.

You northwind, were right. Not a great surprise to me but just wanted to let you know.

73mm so effectively 75.5. Burger! Not going my way!