Trials Bike For Xc

[duane]

Hi,

The summer is coming to Dubai which means 50+ Degrees. Obviously a single speed bike with no seat is about as much fun as a weekend in Guantanamo bay, so my plan is to make my Base TA26 a bit more rideable during the summer months with a usable seat, eight speeds and lighter wheels and tyres. Ideally I would like the base to be rideable enough to take out on the occasional XC ride with some of the local clubs as an alternative to my XC Bike which is great at going up hills, but c5ap at everything else.

I can see the steep head angle being a real irritation after 2 and half hours of gravel single track, other than that the only other draw back I can see is the weight. On the up side I can have more fun in the 'Wadi's' they are dried out river beds that criss cross the UAE.

Has anyone tried this, is it workable or doomed to fail ?

Thanks

Duane.

[poopipe]

I reckon it'll be fine, you'll just end up with a maneuverable XC bike. They don't have steep headangles anyway do they ?

[Krisboats]

My base felt fine whilst doing some more harder cross country. The head angle isn't a problem and its very quick to hop over obstacles etc because of the short chainstays.

The problem however was rigid forks. Unless your planning on using suspension forks and just swap them between riding trials and riding XC then you'll find its like trying to hang onto a neumatic drill. Your head gets bounced up and down so quickly that you can't see much stuff in front of you and this led to me hitting a rock and flipping over the bars mid run.

It WAS fun though!

[Ross McArthur]

I done it on my base. just put a say 80mm travel fork on and youl be fine.

[Thom]

I did it with my moment frame, it doesn't work half bad really, I had problems with tyre rubbing on the front derailluer because of short chainstays, but since you're not running one it should be ok. The other thing is that it doesn't have any holes to mount a bottle cage. I guess you can just use a bag but I hate carrying bags when riding.

[duane]

Hi All,

Thanks for the responses, I am stuck between taking this approach or 'plan B' which is to put some forks with lockout on the XC bike, an 8 speed set up with a decent chain and a hope mono rear hub. Right now this seems to make more sense, theres nothing thats going to downgrade the bikes XC potential where as 'plan A' seems like a step backwards for the trials bike. Backwheel moves with 17inch chainstays and a short top tube must be great training.

Can anyone recommend a reasonably priced 100-200 GBP suspension fork with lockout, my XC frame is quite light and hates droping more than four steps so a dirt jump fork would be complete overkill, I just want something that will get me around fast rocky corners and can be locked out for long climbs and trials. I currently have rockshox judy forks on the bike with lots of preload but they pogo way too much for trials.

Thanks

Duane.

[Krisboats]

Hi All,

Thanks for the responses, I am stuck between taking this approach or 'plan B' which is to put some forks with lockout on the XC bike, an 8 speed set up with a decent chain and a hope mono rear hub. Right now this seems to make more sense, theres nothing thats going to downgrade the bikes XC potential where as 'plan A' seems like a step backwards for the trials bike. Backwheel moves with 17inch chainstays and a short top tube must be great training.

Can anyone recommend a reasonably priced 100-200 GBP suspension fork with lockout, my XC frame is quite light and hates droping more than four steps so a dirt jump fork would be complete overkill, I just want something that will get me around fast rocky corners and can be locked out for long climbs and trials. I currently have rockshox judy forks on the bike with lots of preload but they pogo way too much for trials.

Thanks

Duane.

Put lockout forks on the base frame... job done. Great for riding trials, freat response for quick reaction times while XC'ing. Doing trials on an XC bike with large frame size is soooo hard.

[RobinJI]

Put lockoutLockdown forks on the base frame... job done. Great for riding trials, freat response for quick reaction times while XC'ing. Doing trials on an XC bike with large frame size is soooo hard.

Loskout forks work by locking out the compresion damping within the forks. So trials with the lockout on = Blown compression cartridge or just the lockout turning off every time you do anything depending on the fork.

Id recomend some MX pro ETAs, the marzocchi ETA system locks down the fork, leaving it with only 30mm of travel and very very stiff, so it wont blow up the damping because theres only ever the weight of the fork and wheel pulling down. I know people who use ETA forks for park with the lockdown on and have had no problems.

[duane]

Hi,

Thanks again, I have hardly been in a bike shop or picked up a MTB magazine in 15 years so I really have no idea about forks. The last response makes a lot of sense, I have burst something in my current RockShox Judy forks, I suspect it is to do with damping as the forks pogo and after agressive riding liquid oozes out of the one fork leg.

I have just looked at the Marzocchi forks, the price is right and a recommendation from someone who has used them also helps, but can you tell me is the 30mm of travel the very last 30mm i.e. will my BB be too low with the stiffer setting ? its not very clear from the CRC comments "As you climb, simply flick a switch and the suspension will compress to the ideal height (depending on the riders weight)"

I am just concerned that mr Marzocchi didnt have 13 and a half stone in mind when he was designing the fork.

Any other suggestions welcome too,

Duane.

PS I have just been out on the XC bike and the wife was faster than me, so its 'plan B' for now.

[RobinJI]

MXs will handle 13 stone fine, there tough as hell. As long as your not dirt jumping or flying off cliffs you'll be great .

Also yeah, the 30mm is the last 30, all it does is that when you push down the forks they only come back up 30mm, so turn it on, give a few sharp pushes down to bottom them out and they only come back 30mm. The BB should be alright, as when on 30mm travel they should be about the same length as your average trials fork, if not a little longer.

Edit: Regarding your old forks, it sounds like you have either have blown the rebound cartridge (common problem with older rockshox) and one of your seals has gone. Or if you're lucky you have just blown the seal on the leg with the re-bound damping in (normally the right leg) and the lack of oil is causing a lack of rebound damping.

Edited March 17, 2007 by Dont you Just Hate it When...

[duane]

Hi,

Thanks to your recommendations I have ordered the MX Forks, everywhere I have looked says great things about them.

When I get around to fixing the Rockshox I will use them to upgrade the wifes bike.

Since I have been figuring out how best to convert the XC bike to be more trials or the trials bike to be a bit more XC, its become very obvious that whatever I do to whichever bike, the other one will still be a lot better at its job, so much so that the whole exercise looks like a waste of time, to put it another way I have two perfectly good bikes, why make one of them a half assed compromise.

So the latest and greatest plan is to convert the 9 Speed XC bike to 8 Speed, in order to run a KMC Kool chain. In addition I will change the hub for a hope mono and leave it at that, theres nothing thats going to compromise the bikes current performance plus whenever I get the opportunity to hop around a bit I will have complete confidence in the drive train.

I have a K710 on my trials bike with a spaced out rear mech for a tensioner, the split link would catch on the other cogs if It wasnt a single speed set up, does the KMC K810 Kool come with the split link, and if so is it narrow enough not to interfere with a standard 8speed cassette ? (I want to use the split link)

Thanks

Duane.

[RobinJI]

Unfortunately a K810 will not change gear anywhere near smoothly enough for XC, you'd be best off with a nice sram chain, I've been using a 9 speed one for ages on my freeride bike and I hammer the drive train on that (because I'm so used to riding a singlespeed I just ram down on the pedals before I think of changing gear. haha) and that's held up brilliantly! Would let you keep the 9 speed too. I'd say just put a hope mono and new sram chain on there and leave it.

[duane]

Hi,

I have had the MX Pro ETA's fitted for a couple of weeks now, they have really transformed my XC bike, so much so I am wondering if the frame wasn't originally designed for 100mm travel and then fitted with 80mm forks due to budget. The bike always used to feel tippy on steep technical descents, but now it feels much more laid back. While the new fork has a longer travel, the dropouts are also offset further forward than the old forks. These two factors taken together make the bike feel a thousand times better.

The lockout works as advertised, and with full travel the forks smooth out 40mph stutter bumps and 10mph rocks equally well. the only thing I don't like about them is that V-Brakes seem to have been a bit of an after thought. The optional V-Brake posts screw into thier mounts on the forks this seems like a potential weakness given trials forces, also the V-Brake spring is mounted in a plastic sleeve which is part of the optional V-Brake post, on one of my posts the sleeve occasional moves until the brake rubs, I will secure this with a drop of super glue, but it doesnt give a lot of confidence in the thought that has gone into accomodating V-Brakes.

With a Front Disc these forks would be perfect, and with a front brake booster to share the stress, they may yet be perfect with V-Brakes too.

On the whole very happy and really enjoying some very technical XC riding in the Hajar mountains on the Dubai/Oman border.

Not my pictures and havent been to these exact spots, but to give you some idea, have a look at this guys pictures. If I can talk the wife into camping I will take the trials bike next time.