Hmm, my new frame arrived on Tuesday (on my day off) so promptly built up in the glorious, blazing sunshine, it’s of the ‘a la mode’ long top tube, short stem flavour.

New total length is comparable to my old frame + 50mm stem.

First ride last night at the Gorlech trail near Brechfa.

Granted, the conditions were unpleasant. Peeing down with rain, muggy, very tense from a crappy day at work and I’d forgotten my trail tool kit to make some on the fly adjustments, so seat was about 10mm too low and the rear suspension setting was at 140mm not 150mm as I am using 160mm forks.

Bizarrely my old Nukeproof Mega climbed better, with the forks down at 130mm the bike felt tiny! “Feels” great at 160mm – nicely balanced.

When descending (which is all I really care about – climbs are a necessary evil) it was pretty twitchy! Now, either I was crap loads quicker into corners than I was expecting or the bike just felt nervous.

Someone on here made a comparison between a Jag and a Scooby on some bike tests and I felt the same. The Mega would be serene and the new bike kinda nervous.

Carpark test and bumbling along the bike is comfortable so fit is good, speed and corners are much more ‘intense’ than the Mega.

Apart from the fact it’s essentially a new bike so I should expect some differences, has anyone else made the change to long TT / short stem and had to adjust their riding style / reaction times/effort.

Maybe it’s just that. I just need to exert less effort…to be fair by the end on the final descent (with a little less PSI in the front tyre) I was pushing corners at a greater speed but still with a pretty intense feeling!

Yes, I know how to corner properly!

is an intense feeling good or bad?

Fitted a short stem. Has twitchy handling. Let us know when the penny drops caller 😆

All things being equal a shorter stem should make for a less stable (i.e. more twitchy) feel. Usually all things aren’t equal of course and a move to a shorter stem is usually combined with a move to a slacker head angle (and often wider bars too). But if that wasn’t the case then, yes, it should feel less stable. Whether that is better or worse is, of course, up to you to decide.

Might big change take a while to get used to?

What other things changed? I doubt it was just the TT and Stem length.

I think that the intense feeling wasn’t particularly desirable yesterday given I was so p!ssed off at work. Normally I enjoy a spritley ride!

Head angle dropped to 65deg so one deg down, same bars as before. Overall length was the same as the Mega with a 50mm stem – more or less.

I didn’t think it would be such a step change if I’m honest – just the quickness of the steering was somewhat surprising!

For anyone interested… new Bird Aeris

Assuming you don’t have a sub-750mm bar, are you confident that the fork and shock after set up right?

Apart from the fact it’s essentially a new bike so I should expect some differences, has anyone else made the change to long TT / short stem and had to adjust their riding style / reaction times/effort.

Yes & no in some respects. I’ve ridden a few very long bikes with the super short 10mm stem on top of the steerer tube & always had the same feeling – it would be better if it was slightly shorter and a more normal 40/50mm stem. They force you to ride massively on the front end to get it to bite hard enough in corners – which is fine when racing, but we don’t always want to ride around at 110%.

I ride bike that’s considered long & low still, but not quite at the extreme end of the market – it seems it’s sweet spot is around the 40-50mm stem still for me, I don’t ride all over the front of a bike anyway so it works pretty good 🙂

If you’re finding a bike with a 65 degree head angle twitchy then I reckon there is something wrong. Possibly something wrong with your definition of twitchy 🙂

Bike looks great though.

Personally I’d give it a good few rides first on trails you know well in good dry conditions.
Muddy slippy conditions can make any bike seem like poo.

I did a geometry comparison beforehand the and big differences were:

TT – 24mm longer – swapped 50mm for 35mm stem
WB – 24mm longer
CS – 10mm shorter
BB – 2mm lower
Re – 31mm longer

I was running offset mounts in the Mega so the H/a and BB drop were probably comparable.

Shock and fork felt great! I run two tokens in the Pikes which helped and the new Debonair Monarch was perfect.

I’m hoping it was work stress and shite conditions that caused the step change.

There’s a DH track off Nant yr Arian where I plan to make the real test, I know it well and it’s got bits of everything and by then I’d have used the bike a few more times.

so basically a change to every possible dimension, some changes up to an inch different 🙂

You’ve basically swapped to a different bike and things feel different, this is not surprising, take some time to get used to it, and make some tweaks to see how you get on.

Any change in bar height?

You may be able to tweak it to your liking, or just get used to it, or you may find it’s a change too far, but it’s too early to tell I think, therefore the only reasonable course of action to address this (all?) problem is ‘more riding!’

Ha, yeah, I know amedias, buuuuut when I used the Mega for the first time it felt right immediately. But then it had a slightly more traditional TT and stem length.

Bar height was the same through spacer rearranging, however I’m putting higher rise bars on this weekend to start some tweaking.

On the plus side, it’s slightly lighter and, I think, quite nice looking!

Serious question here, when does a top tube become a long rope tube and when does a stem become a short stem?

My bike (medium) is 23.4″ top tube with 55mm stem. (68ha, 72sa).

Is that long/slack/short?

Curious as my bike is ten years old but really doesn’t seem to be that far off trend.

Or do I “need” to go longer/slacker/shorter?

TT length is largey irrelvant, if a bike has a super slack ST angle it can make a TT appear on paper (and when sat in the saddle) to feel enormous, yet stand up & all of a sudden it become tiny.

Go with reach – most on point current bikes may appear to have TT lengths that arn’t huge, but that’s generally because they have a steep ST angle for better pedalling efficiency, which affects the TT length the opposite way.

Reach never changes with STA, the only thing that affects reach is a longer front centre.

All things being equal a shorter stem should make for a less stable (i.e. more twitchy) feel

Why is that?

Okay then, for a medium frame, what’s a normal reach and what’s a long one? (although I did quote SA as I recognise its influence).

Changes I’d make:-

First rotate that bar

Second buy a secondhand 55mm stem and run the bar in your current position that you prefer. Then rotate it again.

If a bike is ‘twitchy- I’d look at the steering first.

Weirdly on my old bike (SC Butcher) I loved my cut down 730mm Easton Havocs. Changed to my current Commencal V4 and they just felt really wrong. Hard to place why? I’m now on 750mm Havocs and it feels spot on.

So after you’ve done the stem/rotate- try bars?

You could easily sell a secondhand stem on again too.

BTW- it looks gorgeous.

steep ST angle for better pedalling efficiency,

a which for what now?

Okay then, for a medium frame, what’s a normal reach and what’s a long one

Medium frame, I’d expect ‘normal’ reach to be in the 410-430mm area, I appreciate there’s 20mm variation in there but you have to have some generalisations, once you go into 430+ you’re getting into ‘long for a medium’ and 440-450mm is getting into ‘large’ territory.

But there’s always exceptions, and what one person calls long is another man’s normal, for example 440mm reach isn’t massively long, but if that frame was labelled as a medium it would be a long medium, any of this making sense?

Did you test the Bird first? Might simply be your old bike was better for you and how you ride. Just because people on the internet say X bike is the best ever doesn’t mean it’ll suit you.

Also, just because the current fashion dictates long top tube and short stem that doesn’t mean it’s the best option for everyone. It might just be that a longer stem is better for you?

I have a mega TR whcih for my size has a long TT with a 35mm stem, it feels awesome…

lovely foxgloves, and i like that you’ve coordinated your trainers with them. Do you change your footwear depending on which flowers are blooming in your garden? – because that’s a dapper way to roll.

most of the geometry stuff seems to have been covered, so here’s are some variables for you to mull over:

– dustiness: dry trails can be a bit ‘scrabbly’, this will pass as winter approaches (August then).
– tyre pressure: that’s a longish front centre, maybe try a bit less pressure in your front tyre than ‘normal’…?
– fork pressure: as above.

sounds like you’ve got some great reasons for an evening or 2 cocking around with your bike!

if, in the end, you still can’t get on with it. you’ll have no problems selling that frame. and you’ll have had some fun messing around with a new bike for a bit. that can’t be all bad 🙂

Geometry aside that’s a lovely colour

It does indeed look good! Ive just had one delivered too, same colour 🙂

The difference is in the length of the chainstays versus length of the the front centre for each bike. The BB is much more central in the Mega which makes them very stable. If you don’t overthink everything and start shifting stuff round you will get used to it in a couple of rides.

I made the jag v scooby comparison although it was with the Aeris in the Jag category and the Capra as the Scooby. I also backed that up very quickly with ‘I’m not a good enough rider to properly make a comparison’

I also came off a Mega (26in Med AM,170mm deville) to the Aeris (also a Med,160mm pike), From what I can remember, the mega felt more ‘solid’ in the turns although I prefer the way the Aeris feels. I can’t put my finger on why – might be because it’s still quite new and cost a chunk of cash 😉 Agree the mega was a good climber, if you have the CCDB-CS on your aeris, the stock tune doesn’t run that music LSC so you might want to tweak that a bit if it’s feeling wallow-y on the climbs.

I’d stick with it. Mine has a 50mm stem/780mm bars and cornering (especially but not just that) is a different experience/technique compared to other bikes. I always think I just need to ride faster, but that’s probably not the answer.

Just to throw this in as well; last night I dug out my 29er FS which has a 68,5ish HA, is a L frame, has far less travel and it felt very very odd indeed. For 10 minutes. Then the previous 4000km I’d ridden it kind of came back to me. Conclusion I drew was that while the bikes ride differently and do respond to different approaches, they were both bloody ace.

Oh and leave it in 140mm mode, climbs better, not noticeably worse at descending. I got this off Ben (at bird) and he’s right. Stuck mine in 150mm for BPW and it was fab round there but felt ‘less efficient’ on the little climbing we did.

Thanks for the compliments ahwiles, shame they’re the dogs chewing shoes.

I did reduce front tyre pressure on the ride which did improve handling, it was only at 25psi before and I weigh nearly 14 stone so I have to be a bit careful!

Colour is great, I think it’s a cracking looking bike. I really like the chunky welds and full outer cables and the low standover is appreciated.

Crappy looking front mech tab is erm.. crappy.

I’m sure in a couple of rides I’ll wonder what I was waffling on about. First trip to BPW in two weeks so I hope I’ve become acclimatised by then!

Oh and +1 on Shandy’s point. I’m terrible for overthinking things. Weight, foot position, where I’m looking etc. Sometimes you just need to go faster so you ride more on instinct. This might not work for everyone 😉

Hi Alex, just missed your contribution there! Thanks for the additional feedback.
It’s the first bike I’ve not clicked with instantly. When I take my 29er hardtail out, obviously completely different to my FS, I can still hammer it without a second thought.

I’ll mess around with bars, bar height, 140/150 setting and see what happens.

MJ – no worries. I’ve not changed anything on mine. Keep meaning to cut the fork steerer down but haven’t got round to it. I bought a 2nd hand HT the other week on spec, thought it would be the wrong size and the forks’d be rubbish, etc but I just got on it and it felt great. Whereas my Cotic Rocket which was clearly a brilliant bike, I chopped and changed bits for 18 months before giving up on it. Not the bikes fault!

I’m due back at BPW soon (only an hour away) so might try and get a day ticket if you fancy swapping notes in person…

Its pretty common to find yourself ploughing into (and not out of) corners when you first ride an Aeris. The slack HA, low BB and combined with long wheelbase means that the front can seem unweighted as you hit turns hard, giving the feel of oversteer (too fast steering). I’d recommend a few things:

Add 1 more maybe 2 tokens to your pikes. The forks get driven hard as you are pushing through the axle rather than over it, this means that to get the oh so lovely soft off the top with good progression feel that pikes have you need more tokens than a shorter wheelbase fork. Too few and you will have more pressure than is needed, giving a harsher start to the stroke making the forks feel skittish. If you want some more tokens drop me an email – ben@birdmtb.co.uk

Wind your rebound in on the rear shock more than you think is sensible. The shock curve is quite progressive, and that progression needs to be released when you unload the shock. The frame has a decent amount of anti-jack in the design, but especially with the Monarch shocks we find lots of rebound gives bags of traction and a more confident ride as it keeps the bike stable.

People generally report Strava PR slaying fun once they get their Aeris set up right, so keep at it!

Hope that helps.
ben

If you decide to sell it I’ll be very interested ! Email in profile

Surpised no one has said the obvious, if you reduce your stem length you should really go for a wider bar to balance out the feel.

Shorter stem will feel quicker, if you don’t go wider on your bar the steering will be quicker.

Your geometry looks in paper to be very slack, low and long. So its your set up that’s wrong for you, not the frame.

The other area I’d look at would be the stack height, if you’ve gone for a 160mm fork the front end may be too high, so you’ll loose front end grip and the wheel will be light and wandery and skittish.

Wider bar, slammed stem. Ride bike lots. Win.

Bird brothers 🙂

First try of mine tonight, I’m well impressed. Big difference from the 456 I had previously!

Yep, wider bars make a difference in nu skool geo world and as hob nob said you need to lean over the bars that bit more, it just encourages you to go fast ime