Hey everyone! Welcome or welcome back!
Do you guys use a Chainguide with your bike?
I haven't for the longest time
but recently I found out that no one else but Shimano has one of these.
Believe it or not this is in their XTR lineup and I thought I would give it a try, so let's check it out!
Out of the 3 versions of this chainguide the one that I needed
is the ISCG tab one because I do have those tabs on my frame.
And be warned that this is only for 52 mm chainlines are specified over here.
But can we push the design on a 55 mm chainline bike like this one?
Well stick to the end of the video to see if that works.
Also if you like this type of videos make sure you smash that thumbs up button
because it really helps me with the YouTube algorithm.
As for the uses - somehow they only put Cross Country and Enduro and nothing in between.
On the back of the box you're gonna see that this is made in Japan and you're gonna see the product code.
But again all 3 product codes can be seen here up front with the 3rd one being for ISCG tabs.
In the box you're gonna get - the chain guide
and this big user manual.
Interestingly in here what they say is just to go to the local bike shop
because you need a dealer manual to install this.
So, you know me, let's just do this together then!
Here's the chain guide first of all, and yes it does say Shimano over here
and in the second tiny bag
here is the two retaining bolts and these look like spacers.
Together with the two bolts provided they weight 9 grams
and if I add the actual chainguide we're gonna get to 41 grams altogether.
The last chain guide that I used was a OneUp and this seems to be a bit more premium
you can see that Shimano logo up top.
This is probably CNC'd aluminum.
If you flip it over you're going to actually get the part number SM-CD800-I
As usual there's not too much to these chainguides
First of all you have that 4 mm bolt over there
so by tightening it you just lock the top of the chainguide into position.
You have this adjuster here, you see this wheel, that's gonna allow you to move this up and down I think about 2-3 mm.
As for the spacers included, you're getting two 1.25 mm and two 2.5 mm spacers.
The way you use these would be inserted between the chainguide and the ISCG mount.
and secure it in place with the bolts provided.
Also here on the inside of the chainguide top you have those 2 grooves.
You're supposed to align your chain to one or the other
depending on whether you're using it for hardtail or full suspension bike.
It's going to be interesting to see how that works in my case
because I am using an 32T oval and this is going to vary between 30 and 34 tooth chainring diameter.
The two bolts don't have Loctite (blue) on them so make sure you put some
and Step 1 of the install recommends to shift to the hardest gear and with the chain in that position
install the chainguide loosely using the 2 top ISCG tabs.
Now the only problem that I have in case of this frame
is that my chain guide is actually a bit too tall over here,
so it's gonna touch onto my swing arm!
How long is too long for my frame?
Well this part here of the chain guide is 7.5 cm so that would be exactly 3 inches.
Chainguide seems to fit well on this other bike and one thing I thought I would bring up is
this gap that Shimano recommends not to be wider than 3 mm.
I set it up to 2.7 mm which is close to the max recommended
and with the chain on my smallest cog I'm gonna take a look at this
and make sure that the chainguide doesn't actually touch the chain.
Next, take a 4 mm Allen and install the chain guide, I wouldn't tighten it yet.
and you're gonna see that you have quite a bit of wiggle room
and Shimano recommends using those two tiny grooves to install it parallel to the chain in this position.
The 2 little grooves are also used to adjust your chain guide up and down
and what they say is to use the top groove for hardtail
and the bottom groove for a full suspension bike.
For me it's also the complicated matter of having an oval
so I'm gonna just to move it here onto this 34 tooth position (of chainring)
slide it down so the top aligns to the top of the chain
and tighten this up.
Time to look down and see if the chain touches the chain guide
So no need for further adjustments everything is fine but looks like my chainring is bent, go figure!
The downside of using this with an oval is that you can see how the chain almost comes out
of the chainguide in that 30T position
but I don't think it's a big deal.
Time to move the chain to the other extreme and there you have it
chain in the largest cog and even with my wobbly chainring
I'm still okay because the chain guide pretty much starts where the chain bends to make for that extreme chainline.
After doing all that test if you need to fine adjust your chainguide
all you have to do is loosen this up
use that fine adjuster to move this chain guide further or closer to the chain
and finally tighten this up again
while holding on to the adjuster because otherwise that will rotate with it.
And here's the chain of the two extremes first chain on the largest cog
and second extreme chain on the smallest cog of the cassette .
No problem whatsoever so this is very easy to install but the big question remains:
even though this was designed for 52 mm so Boost bikes,
can we install this chainguide on a bike like this
that actually uses 55 mm chainline to accommodate for those larger tires in the back?
Well after installing those 2.5 mm spacers right here behind the chainguide
I can tell you that this works just fine. chain is nicely centered.
I have plenty of adjustment over here
this being on the 55 mm chainline.
52 mm work just fine and I would think that
if you install this chainguard on an older 49 mm chainline (non Boost) I think it would be fine as well!
So there i have it guys, Shimano being as usual a bit more conservative.
Their design can be stretched to work on pretty much any modern bikes that we might be riding today.
Do you guys use a chainguide?
Do you use this Shimano, do you use an OneUp, absoluteBlack?
Let me know in the comments below.
Also if you found this useful don't forget to like subscribe comment
and until next time hope to see you on the trails!
Cheers guys, cheers!