2020 Gas Gas TXT 250 Clutch Question

[Dzl850]

I recently purchased a 2020 Gas Gas TXT 250. I have about 15 hours on the bike. I have the freeplay adjusted properly at the perch and am running the recommended 75w/90 gear oil, which was changed after about 2 hours.

With my clutch lever fully engaged to the bars, the bike wants to creep forward. If I put it on a stand the rear wheel turns when in gear and the clutch lever engaged to the bars.

Is this normal? I am new to trials and to this bike. I find that it actually helps me when balancing etc., but don't want to smoke my clutch.

I did a search before I posted, and I couldn't seem to find anything to answer my question.

Thanks in advance for any help!

[sherpa325]

The oil does make a difference and the lighter the oil the better. I use ELF htx 740 , another good light oil is GRO Gear Extreme 75W. There are ways to adjust the clutch inside the case, but I would change the oil first and see if that works.

Cheers Greg

[Dzl850]

Thanks Greg! I will try the ELF or GRO.

[kurtas]

If you have stubby fingers you may find that it is difficult to fully disengage the clutch without having a tiny amount of slip.

You should be able to easily push the bike backwards however even though it is slipping very slightly.

Bit of a theme with the diaphragm clutch that Gasgas and others use that there doesn't seem to be the positive engagement that you get with the basket style clutch of say a Beta or Montesa.

[lineaway]

 So you have had other hydraulic clutched bikes? Most people always get the lever adjustments wrong and ATF works better than any other oil.

[sherpa325]

With the Elf oil I can find neutral easily and the clutch does disengage, however that's not the case with ATF

[Dzl850]

Thanks for the feedback.

For comparison I have a KTM 300 with hydraulic clutch. The clutch fully disengages.

I have played with the lever adjustment on the GG but that didn’t affect the creep I get when fully engaged. But I can also push the bike backwards with the clutch engaged.

I am a newbie to trials and the GG. I use the clutch a lot, much more than any bike I have ever ridden. My two concerns were: is this clutch action normal, leading to - if not normal how do I fix it and will I damage the clutch?

Thanks,

Brian

[lineaway]

 You will not damage the clutch, in fact you probably need to burn the clutch in a bit for it to work properly. The Gasser clutch is quite touchy on clutch pack thickness. Go to a trials and ask the top riders what they run for oil.

[Dzl850]

Thanks Lineaway. 
All trials events are shut down in my part of the world due to Covid. But my questions have been answered.

Thanks all.

[lineaway]

Actually your best rider just finished the Ute Cup last weekend with 3 points on a Gas Gas.

[boofy]

Use putoline gp10 in gear box as factory riders use, atf can swell plates.  ?

[drca]

On 8/20/2020 at 11:43 AM, Dzl850 said:

I recently purchased a 2020 Gas Gas TXT 250. I have about 15 hours on the bike. I have the freeplay adjusted properly at the perch and am running the recommended 75w/90 gear oil, which was changed after about 2 hours.

With my clutch lever fully engaged to the bars, the bike wants to creep forward. If I put it on a stand the rear wheel turns when in gear and the clutch lever engaged to the bars.

Is this normal? I am new to trials and to this bike. I find that it actually helps me when balancing etc., but don't want to smoke my clutch.

I did a search before I posted, and I couldn't seem to find anything to answer my question.

Thanks in advance for any help!

I have a 2013 Gas Gas TXT Pro 250 and my experience is that there is always a little bit of clutch drag on the bike (and I believe that I am not the only one).  It's worse when the bike is cold (cold oil).  Too much drag can be not only annoying but possibly dangerous as it can cause the bike to stall at inopportune times.  

Oil wise, some people recommended ATF (never tried, or the Elf brand (very hard to find in the US).  I use Maxima MTL Transmission Fluid 75wt ($10 at my local Cycle Gear) and I've been pretty happy with it.

It's unlikely that you will "burn" your clutch on a trials bike short of riding stupid!

Adjustment wise, you might want to try the shortly levers like the Apico's Flex levers.  They allow to adjust independently the reach and engagement point.  That might help too.

 

The Gas Gas clutch is actually pretty good and better than most traditional spring designs.  The diaphragm clutch is used by GasGas, Ossa, JTG, TRS, Vertigo, Sherco-Scorpa and Electric Motion.

The thing to know about the Gas Gas clutch is that it's highly (and easily) tunable by adjusting the clutch pack thickness (3 fiber plates + 2 steel plates):

• Thinner pack makes for an easier pull and a slower engagement (which is what most riders at the beginner to intermediate level will need).  If you go too thin, you'll get clutch slip tho.
• Thicker pack = harder pull at the level and much faster engagement. 

By fine tuning the thickness of the clutch pack you can go from a bike that will be mellow and easy to ride to a bike that will want to jump up 4' ledges when you dump the clutch.  At my level (SI), and age (!), I go on the "easy" to ride side.  But I have experimented with various configuration and this is definitively something you can feel at any level.

How thick or thin should you go?  Below are Gas Gas recommendations.  Honestly I don't understand why the numbers change depending on the year, but they should be a good place to start.  And in my experience, these are really guidelines and considered as starting points for your own experimentation.

How you change the pack thickness?  You buy steel plates of different thickness (as a set or individually) and swap them in / out until you arrive to a combination that you like.

Hope this helps.

DC

[Dzl850]

Hi DC,

Thanks for the feedback. I did end up purchasing some shorty levers from Lewisport. They are basic Jitsie levers and use rubber/plastic bushings. I like the shorty's but I need something of better quality. Will see if I can find the Apico Flex levers you referenced.

I have been running the Motorex Prisma ZX Gear Oil that came in the bike and I experimented with Mobil 1. Went back to the Motorex.

I think the problem was with me as I was not familiar with the trials clutch, and come from an enduro background.

Appreciate the information on the clutch adjustment. I will keep that in mind as I get better and look for different tuning.

All I can say is that I seriously enjoy this bike. It's like being a kid again, other than the falls hurt a lot more!

Thanks again,

Brian

[Sum]

Hi Dzl850,

I also a newbie and just bought a 2020 TXT 280 and have exactly the same issue.

Even if I pull the clutch all the way in, it drags a bit. One-finger operation makes it even more noticeable (because I can't pull the lever to the bar).

However, it is not bad enough to stall the engine and becomes slightly better as the clutch plates warms up.

I have a similar symptoms, especially when cold, with my KTM 150 and when I bought a Midwest Mountain clutch lever, the instruction says that it is normal to have slight drag until the clutch warms up and thus adjustments have to be done after it gets fully warmed up.

The drag of my TXT is slightly worse than the KTM but as long as it doesn't stall and the bike can go backward in slopes, it may not be a big issue.

I will continue to fiddle with the setting and Apico Flex levers do look great for the adjustability (I can't find where I can buy them, tho).

Let's see how it goes as the bikes break in.

 

[nigel dabster]

there are 3 settings on the clutch this might affect drag