miny Posted May 14, 2017 Report Share Posted May 14, 2017 I have a 2015 TXT PRO 125 and feel the clutch is a bit heavy. Is there a remedy for this? I have seen the video on youtube of the 2009 model having the clutch plates thinned, is this the answer for the 2015 model also? Quote Link to comment Share on other sites More sharing options...
miny Posted May 14, 2017 Author Report Share Posted May 14, 2017 (edited) What's DP for the ignorant please? And thanks very much for the advice Edited May 14, 2017 by miny Quote Link to comment Share on other sites More sharing options...
lineaway Posted May 14, 2017 Report Share Posted May 14, 2017 Just put the front tire against an obstacle in fourth gear and burn in the clutch. Instant fix without any more work may take a couple attempts as most people are to chicken to get after it properly. Quote Link to comment Share on other sites More sharing options...
billyt Posted May 15, 2017 Report Share Posted May 15, 2017 So as I stated on another post here I am working on a 2003 Gas Gas for a newer rider. His clutch pull is VERY hard. I have lots of technical knowledge around Beta & Montesa clutches but a newbie to the Gas Gas diaphragm clutch. After listening to all the advice videos and blogs out there I am now totally confused. Here is why. Everybody states a clutch pack thickness of around 9.75mm there is even videos showing a guy holding a clutch pack in his hand and measuring the pack. However the cut away technical drawing from Gas Gas clearly shows the 9.75mm with the pack under pressure Not in a person hand under NO pressure. I measured the loose vs under pressure of a clutch pack and its is around 1mm compression differential. Why is everybody quoting 9.75mm with no pressure? 1 Quote Link to comment Share on other sites More sharing options...
billyt Posted May 15, 2017 Report Share Posted May 15, 2017 (edited) Not sure what you are saying here. I asked a basic question of why Gas Gas riders quote 9.75 for plate thickness uncompressed (meaning held against each other) when the official Gas Gas drawing calls out for 9.75 in a compressed state. I have two clutch baskets, one on the bike and one on my workshop bench. I can assembly in my hand a variety of fibre plates and metal plates to make up the 9.75mm. However once I install them and tighten everything up ( clutch on my bench) I can then measure the outside of the tabs on the fibre plates and the pack thickness is now 8.70mm. Edited May 15, 2017 by billyt Quote Link to comment Share on other sites More sharing options...
billyt Posted May 15, 2017 Report Share Posted May 15, 2017 (edited) The sectional drawing is from a technical bulletin from Gas Gas themselves. I have that 2010 TXT manual already. Not disputing what you are saying. I looked at the drawing again this time with a magnifier glass (old eyes). It is a compressed measurement and it is not from outside of tab to tab but rather from friction surface to friction surface. Makes sense now. The bike is a 2003 TXT Pro 280 I re -measured from inside the hub base to the inside of the large metal ring. So, 9.75 clutch pack in hand and 9.5 in compressed state. Still some compression going on there and still not 9.75mm compressed as it calls for. Seems it needs to be 10mm uncompressed to get 9.75 compressed. Are people bending those fingers to get the 17mm? Is that measurement from the bottom or top of the finger? How does the the finger height affect clutch pull in the way hardness or softness? I can see it affecting clutch lever travel but stiffness??? What I missing here? Edited May 15, 2017 by billyt Quote Link to comment Share on other sites More sharing options...
pauls320 Posted May 15, 2017 Report Share Posted May 15, 2017 Quote Link to comment Share on other sites More sharing options...
billyt Posted May 15, 2017 Report Share Posted May 15, 2017 (edited) Need some aspirin Paul. I do, I have to fix a friends 2003 TXT Pro 280 with a 2002 TXT 200cc clutch hub and clutch pack in it that some body swapped out a year ago. Needs a VERY strong hand to pull the clutch in. Need to put the original clutch hub assembly and clutch pack back in it. Took the clutch pack apart and all the fibre was lifted of the fibre plates in one piece. It had two 2mm metal plates in it and three fibre plates with six separate fibre rings. You can see the images down below of one fibre plate with both sides of the fibers completely lifted off the plate. On the other picture you can see the glue remnants. Has any Gas Gas owners experienced this seperation of clutch fibres before? What a mess. Edited May 15, 2017 by billyt Quote Link to comment Share on other sites More sharing options...
stpauls Posted May 15, 2017 Report Share Posted May 15, 2017 Before you do any of the above, you have 6 springs in your clutch. Remove 2 of them. It will not slip, because the same clutch is used on the 300cc bikes, which have 3 times the power, but it will make your clutch pull 1/3 lighter. Make sure that the springs you remove are opposite each other. Quote Link to comment Share on other sites More sharing options...
baldilocks Posted May 15, 2017 Report Share Posted May 15, 2017 A diaphragm clutch doesnt have 6 springs, it has a single beville spring. The spring was changed, I think in 2006, for a lighter one. Fitting the later one will help with the clutch feeling heavy. I agree with Billy on the measurement when not under compression. I did a friends recently at 9.9 just by hand, the clutch is very light but doesn't slip. Quote Link to comment Share on other sites More sharing options...
billyt Posted May 15, 2017 Report Share Posted May 15, 2017 stpauls As Oni Nou says this is a Gas Gas diaphragm clutch with only one spring in it. Now we know why you where banging your head against the wall, cereal boxes are getting harder to open these days. Quote Link to comment Share on other sites More sharing options...
billyt Posted May 15, 2017 Report Share Posted May 15, 2017 I think the main reason people measure it in the hand is due to the fact that it is a pain in the ass to remove the whole clutch assembly to measure it under compression so they just do it by hand. I was fortunate enough to have two clutch hub assemblies to play with one on the bike and one on the bench. Quote Link to comment Share on other sites More sharing options...
baldilocks Posted May 15, 2017 Report Share Posted May 15, 2017 (edited) 5 hours ago, oni nou said: YesManual states...the clutch pack thickness must be between 9.75mm and 9.85mm for correct operation....the txt pro MANUALS from many years of the pro quite clearly show a photo image of the clutch plates being measured with a Vernier calliper held together as a pack in a hand and not in the basket and compressed by the spring Re: 9.9 the clutch is very light[that depends on the strength/physical condition of the person of course] does not slip....I have put lots of packs in at 9.75mm just by hand and the clutch is very light and does not slip. If you put a clutch pack in the basket measured at 9.9mm then it will load the belville spring more than a clutch pack measured at 9.75mm when the spring and pressure plate clamp the pack together; so will be less likely to slip obviously as it is clamped with more pressure.... for the same reason the clutch pack that measures 9.9mm will also be heavier to pull at the lever than a clutch pack that measures 9.75mm as it is putting more pre load into the belville spring in the clamped state before the clutch slave cylinder starts to move the pressure plate to release the clamping pressure on the clutch plates. The correct clutch pack thickness should give you the correct finger height if the fingers are not damaged [17mm according to the manual] which is the a major factor in the way the clutch feels at the lever ie light or heavy] THE NEXT PARAGRAPH IS VERY IMPORTANT IN RELATION TO THE GOAL OF MAKING THE CLUTCH PULL LIGHTER From my own experience of pro clutches I can tell you that the pull on a pro clutch with a pack thickness of 10mm has a very heavy clutch lever pull[painful after 30 mins use] [but when replaced with a clutch pack measuring 9.75mm as per the manual then the clutch pull is very[and I mean very] light and joy to use and does not slip .[No other parts were changed it has the same belville spring and the same paddle fingers and pressure plate]. Enough of this nonsense,To end this; anyone who thinks that measuring the clutch in the basket is correct..... is WRONG........this information comes from a man known as Factory Kev....he is THE mechanic at GasGas UK the importer of GasGas trials bikes since around 1988 he has worked there for around 10 years and prepares the bikes of Michael Brown and the GasGas UK team and has prepared the bike that James Dabill used in 2010 for the WTC and BTC...... from his mouth come the words" measure the clutch pack in your HAND"...." NOT in the basket compressed."...his recommended clutch pack measurement is 9.8mm [measured with the clutch pack held in the hand not in the clutch basket compressed] which as anyone who is following this properly will know is inbetween the measurements of 9.75mm and 9.85mm as stated quite clearly in the manual. Yes Oni I get all that. The point I'm trying to get across is based on my experience of fitting a pack measured at 9.9mm with a digital Vernier. This should not have been a light clutch, I understand what you are saying. The fact it did means to me that how hard you compress the plates using the Vernier will make a difference to the measurement. In addition when the thickness is this critical measuring a pack soaked in oil probably makes some difference when its squashed, ie it may compress .05mm more as you drive the surface oil out. I used a combination of used plates to get to 9.9mm. A new dry clutch pack may not compress as far using a Vernier ? The DP pack my friend bought measured at 10mm when removed from the box, this is sold as ready to fit, presumably as its expected to bed in by 0.15mm relatively quickly ? To get back to the original question just go an burn the clutch up some 4th gear hills, if it doesn't work you've still had more fun than trying to sand a fibre plate Edited May 15, 2017 by baldilocks Quote Link to comment Share on other sites More sharing options...
lineaway Posted May 15, 2017 Report Share Posted May 15, 2017 (edited) I tried to get you to call me Billy but since deleted my number. The correct way to measure yours was by the finger height. The best number to attain is 18 mm. You can do that with thinner steel plates or by skimming the friction plates. And by the way the plates seperating was very common on Gassers. Edited May 15, 2017 by lineaway 1 Quote Link to comment Share on other sites More sharing options...
cabby Posted May 18, 2017 Report Share Posted May 18, 2017 The OP in the topic is a woman and very slight, so I thought she just needed to man up with her clutch finger but tonight I felt how heavy it is myself, jeezo, it's the stiffest clutch pull I've ever felt. Quote Link to comment Share on other sites More sharing options...
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