My Tushy Is Very Sensitive!

[copemech]

At the risk of feeling like Rappers here, taking his weekly flogging for his opinions, I am going to throw out a few things that may or may not draw opinions from others that may be interisted. As the title states, much of this is "seat of the pants" as I am not fortunate enough to have a DYNO sitting in the shed to prove or disprove anything! Some of this would need "Myth Busters" money to prove or disprove!

Firstly, Spark Plugs make a difference!

I believe they do! Many bikes run the standard plug such as a BP5ES closed down to as little as .020 or .5mm in an effort to accomodate the low power ignition systems on most bikes. You simply have to take advantage of what is there I think!

I have run the BP5EVX plug for several years now OPENED UP, taking advantage of its superior electrical properties and running at .027-.028(.7mm) providing better electrical flamefront (ignition) making for easier starting, better low end power and less fouling problems. I have even taken these plugs from bike to bike over the years without normal replacement. Yes they cost more! And I am not quite sure about the Irridium plug as it has a resistor which may defeat some of the electrical properties of the non resistor VX, but I do believe you could run it at .6mm at least with no problems.

Secondly, Addition of small quantities of Acetone to fuel to improve atomization.

You need to get on the net and do your own research on this. It is a topic upon itself, but I think it works in all vehicles. Maybe something to consider? I am somewhat conservative on these issues myself. There is much info out there! All I can say is that I have done it for the last couple years without problem. Seems to work!

Thirdly, Running ATF in a standard clutch and gearbox!

This is a topic which may vary by bike, but there are two things I can state with reasonable certainty!

1- the clutches in any automatic transmission are not designed to slip(much) or they will burn up! Or the oil will burn! Therefore you will get more bite! Good for some, not for others!

2- The premium ATF these days is that fully synthetic offered for Allison C-4 trannys! If it does not meet that spec, I would not use it! It is good stuff, but I am not sure it is great for all. A more common gearbox oil may provide better progression in the clutch feel! I am currently considering doing some experiments using friction modifiers in the ATF to "fine tune" to taste! Anyone done this?

Seems as though most of the testing on this stuff is "seat of the pants", I like to experiment a bit, but still remain conservative and go with what works and is proven. But at the same time it seems some of the folks around are soo hard headed they would not consider doing anything different and many still run bean oil at 40:1.

That should do for now, next I'll start up on Carbs!

Edited March 6, 2008 by copemech

[dan williams]

Yes the sensitive tushy. On that front although it is not strictly mechanical I have one suggestion to prevent the mad case of monkey butt from resting on a trials seat RE: fender.

Spandex bicycling shorts with the built in chamois padding fit under riding pants and provide built in cushion that doesn't get in the way. I'm talking the road rider shorts here. Once you get over the initial feeling that you're wearing a diaper they are quite comfortable. Your sensitive tushy will thank you.

[feetupfun]

Secondly, Addition of small quantities of Acetone to fuel to improve atomization.

You need to get on the net and do your own research on this. It is a topic upon itself, but I think it works in all vehicles. Maybe something to consider? I am somewhat conservative on these issues myself. There is much info out there! All I can say is that I have done it for the last couple years without problem. Seems to work!

Acetone addition not recommended for fibreglass fuel tanks

[ham2]

Acetone addition not recommended for fibreglass fuel tanks

Acetone?? That's a surface tension reducer?Yes?

I've looked into this before.

I've used it in my car before and It seemed to give a little more MPG, never noticed any performance enhancement though.

In your bike,you would have it sitting in the tank for days or weeks absorbing moisture?..no thank you.

I wouldn't even add it to my bike if I used my bike every day .

[tilertrialler]

just treated myself to a bp6evx for my beta ,previous posts seemed to think they were now unavailable, but i have just got one from pro parts direct from ngk, cost me just over

[biffsgasgas]

Cope!

First; Spark.... Have you ever measured dwell off of your coil with a scope? Come on now i know where you work and some of your resume. Change plugs look at dwell. Change mixture look at dwell. Increase and decrease gap look at dwell. Get out your gap spark tester and measure. (doubt you have room for that on a sherco but its a thought) You bring up a good point here and i think you might find some answers in dwell. Tell ya what. This weekend I will grab one of our IDS's and a VMM here from fomoco and take some screen shots of what i have on my 04 gg. I am not sure if you have capability of something similar but this is interesting to know whats going on in there.

Second; friction modifiers... My roommate worked very closely with borg warner with their torque on demand system. You guys have a similar system on jeep. He has a montesa which are known for their clutch drag. As it turns out chain tension and that really expensive stuff was the answer to his problems. I use straight dexron and change it ever 8 hours or so of ride time. One night before an event i needed a quart and some turbo blue for the bike. I thought i would kill 2 birds with one stone and picked up a quart at the station. When i got home i looked at the bottle and i kid you not it stated "Almedes Oil Company" and it had no sae markings or anything. Due to my lazyness i threw her in so i wouldnt have to make two trips. Smelled like 80-90gls, was red, poured like 30 weight.... In the morning i drained it in fear of the unknown. Becarefull because the sulfer in friction modifiers (such as dana 60 70 or 80 additives) can set permanently in clutches and cause too much slip and its hard to get it out of the fibers once its set in.

I am part of the fuel injection generation so i would be real interested to hear the carb setup edition.

I am going home to shovel some beautiful michigan snow now.

--Biff

[paulthistle]

The resistor, I believe just cuts down RFI. On yamaha's for the last ten years, running a non resistor can cause a ignition malfunction. Once stopped will crank up and run fine. With the close proximity of the ignition control boxes, I would say the resistor would be cheap insurance.

I am running the BPR5EIX. I have not fouled a plug in 2 years. My son has fouled one on his beta 80 in a year and a half.

Great oils are created. You can run auto trans oil or whatever, and I'm sure you will save a couple of bucks. While you are at walmart why don't you pick up some mixing oil? It is rated the same.

Maybe thats why your tushy is sensitive, its been tight for so long.

[copemech]

Cope!

First; Spark.... Have you ever measured dwell off of your coil with a scope? Come on now i know where you work and some of your resume. Change plugs look at dwell. Change mixture look at dwell. Increase and decrease gap look at dwell. Get out your gap spark tester and measure. (doubt you have room for that on a sherco but its a thought) You bring up a good point here and i think you might find some answers in dwell. Tell ya what. This weekend I will grab one of our IDS's and a VMM here from fomoco and take some screen shots of what i have on my 04 gg. I am not sure if you have capability of something similar but this is interesting to know whats going on in there.

Second; friction modifiers... My roommate worked very closely with borg warner with their torque on demand system. You guys have a similar system on jeep. He has a montesa which are known for their clutch drag. As it turns out chain tension and that really expensive stuff was the answer to his problems. I use straight dexron and change it ever 8 hours or so of ride time. One night before an event i needed a quart and some turbo blue for the bike. I thought i would kill 2 birds with one stone and picked up a quart at the station. When i got home i looked at the bottle and i kid you not it stated "Almedes Oil Company" and it had no sae markings or anything. Due to my lazyness i threw her in so i wouldnt have to make two trips. Smelled like 80-90gls, was red, poured like 30 weight.... In the morning i drained it in fear of the unknown. Becarefull because the sulfer in friction modifiers (such as dana 60 70 or 80 additives) can set permanently in clutches and cause too much slip and its hard to get it out of the fibers once its set in.

I am part of the fuel injection generation so i would be real interested to hear the carb setup edition.

I am going home to shovel some beautiful michigan snow now.

--Biff

Biff brings up good points here!

Dwell? Burn time? Squiggly line theory? Good god man, we have not had O-scopes that worked on anything in the field in at least 15 years with COP! Theory is no longer tought or used! We have on board computers nowadays that tell everything we never wanted to know and nothing we do!(Refer to recent discussion with zone tech rep on same topic) Secondary problems that drive things crazy due to feedback cannot be viewed or monitored! At least not by anyone that has to try to actually fix them!

Good idea though if you have something that will work on yours and ZIPPYS !

"My roommate worked very closely with borg warner with their torque on demand system. You guys have a similar system on jeep. He has a montesa which are known for their clutch drag. As it turns out chain tension and that really expensive stuff was the answer to his problems."

I am not quite sure what you are saying here, is he using the transfer case fluid? or something? And yes, we have different fluids that rely upon progressive or modulated clutches to apply power(hopefully smoothly) and I am not sure what additive packages they use. There could be a LOT of experimentation there, more than I would like!

Clutch action is a very personal subject as well. I think it basically falls into two classes of riders.

Those that want and need smooth progressive action and those who want and need things to happen NOW!

And the two should not be confused! I think there will allways be a tradeoff there.

Point being that those that may run cheap ATF are screwing themselves!

[copemech]

The resistor, I believe just cuts down RFI. On yamaha's for the last ten years, running a non resistor can cause a ignition malfunction. Once stopped will crank up and run fine. With the close proximity of the ignition control boxes, I would say the resistor would be cheap insurance.

I am running the BPR5EIX. I have not fouled a plug in 2 years. My son has fouled one on his beta 80 in a year and a half.

Great oils are created. You can run auto trans oil or whatever, and I'm sure you will save a couple of bucks. While you are at walmart why don't you pick up some mixing oil? It is rated the same.

Maybe thats why your tushy is sensitive, its been tight for so long.

It is pretty well established that some systems and manufacturers require resistor type plugs to protect their systems from secondary spikes, others do not and to me and my simple logic, the added electrical resistance is nothing but an additional obsticle for the already weak system to overcome and if not neccessary, probably not in the best interist of providing the goal of igniting fuel! The available voltage and the compression ratio will be the limiting factors upon just how well you can reliably perform this act at a given gap of the plug!

Secondly, I doubt you save any money running a top performing fully synthetic ATF and would not recommend using anything less. Point being that you may screw yourself in the process in terms of clutch feel and such.

As an example, several years ago I remember the factory frame stickers on the Sherco saying "Sherco recomenda Valvoline"

Now this is a Sureflex clutch in a Sherco and the only factory spec was and still is 10-40 as best I recall. Over time the sticker has changed to a simple Ipone logo, but the clutch has not changed. Now I ask you , what the hell does all that mean?

I can tell you that at that time I ran Valvoline synthetic motor oil with no problems and possibly better feel than the new bikes, once again depending upon what you want and considering the fact that they have changed to the mid length levers which have a different and shorter "sweet spot'! It all comes into play here!

[biffsgasgas]

"My roommate worked very closely with borg warner with their torque on demand system. You guys have a similar system on jeep. He has a montesa which are known for their clutch drag. As it turns out chain tension and that really expensive stuff was the answer to his problems."

I am not quite sure what you are saying here, is he using the transfer case fluid? or something? And yes, we have different fluids that rely upon progressive or modulated clutches to apply power(hopefully smoothly) and I am not sure what additive packages they use. There could be a LOT of experimentation there, more than I would like!

Oops forgot to finish my point.

A lot of techs out there have played with friction modifier in their tcases to try and get awd shudders to diminish. They end up taking out clutches or causing chatters and engagement periods to be more harsh. My roommate tried a few different mixtures and ended up with no clutch plates after a while. He finished his experiment by getting a new clutch and tightening the chain using the specified oil and wala it worked like a champ.

Becareful because this might make a good day of practice a long day of walking around. There is a lot of science in those fluids. Besides i thought that sherco clutches were flawless?

--Biff

[copemech]

Oops forgot to finish my point.

A lot of techs out there have played with friction modifier in their tcases to try and get awd shudders to diminish. They end up taking out clutches or causing chatters and engagement periods to be more harsh. My roommate tried a few different mixtures and ended up with no clutch plates after a while. He finished his experiment by getting a new clutch and tightening the chain using the specified oil and wala it worked like a champ.

Becareful because this might make a good day of practice a long day of walking around. There is a lot of science in those fluids. Besides i thought that sherco clutches were flawless?

--Biff

I agree and have been skiddish about trying thak Dana lube for reasons stated, now that x-fer case fluid, pre mixed for smooth progression? Sounds of interist and I have lots of it! One would presume that it may be more better than standard motor oil?

Being no Gasser expert, all I can say is that since they came out with the lighter spring plate a couple years back, I have ventured out and taken a few spins on various bikes, 125, 200 250 and 280. Seems like every one is different and much depends upon how they were set up at the factory. Some great, some stiff? I do not understand them totally, just seems some need a bit of TLC and fluid is not going to do it! I hope Stoodly has all that figured out?

[biffsgasgas]

Sorry Cope i never got to it this weekend. I was busy working on my Greeves/tl125 project. I started welding and brazing and just couldn't stop! hahahaha. If i find a free moment i will get some scope readings. Just wanted to let you know that i have not forgotten.

--Biff

[jse]

Being no Gasser expert, all I can say is that since they came out with the lighter spring plate a couple years back, I have ventured out and taken a few spins on various bikes, 125, 200 250 and 280. Seems like every one is different and much depends upon how they were set up at the factory. Some great, some stiff? I do not understand them totally, just seems some need a bit of TLC and fluid is not going to do it! I hope Stoodly has all that figured out?

Mark,

It's real easy to get nutty about what fluid to run in wet-clutch bikes, especially Trials bikes, whose clutches get a real workout. The same goes for suspension where, for instance, I will choose a different type of shock fluid depending on (irrespective of other factors, like viscosity, and that would depend on how that viscosity was measured-and at what temperature, the riding style of the rider and the general type of track the bike was used on etc.) if the shock body was steel, raw aluminum, anodized aluminum, treated or non-treated magnesium, coated (and it depended on the type of coating) etc. See, Mark, with all this kind of stuff in my head, you now know why I act so goofy....

Here in the U.S. a good place to start is the brand importer as they are kinda like a "hub of information" (or should be) that will get feedback from dealers and riders. I like to recommend fluids that are easily available to the average rider and that I have had personal experience with and not the space-age stuff made with unobtainium that couldn't pass a radiation detector my aerospace engineer buddies are always trying to con me into trying. I've generally found that a light tranny oil, changed frequently, has given me the best performance. For the GasGas earlier models, like the "Edition" engine, I ran DexronIII ATF in my JTR370 (which is about 7.5 weight), for my 02' 280 Pro (with the Magnesium engine) up to the 05', I think (when they changed to a thinner Bellville spring) I run the GM AutoTrak II transfer case fluid, and the 06' on up seems to work well with Ford Type-F ATF, which has a little higher heat tolerance and a little more "bite". If I had the DOT-3 clutch, I'd switch to DOT-5 (Silicone, which seems to have a little better lubricity than the brake fluid) but that entails flushing out the whole system, not just bleeding off the line and dumping new fluid in the M/C reservoir. I like to change the fluid every 5-10 hours of use or after a nasty, wet Trial.

Theres other things I do, like run a magnetic plug (like the lower one for the case drain) in the upper sidecase oil filler to catch all the fine metallic particles any engine normally makes, use a modified Suzuki lever that has a flat blade that's more comfortable for me, polish the servo and master cylinder bores with ultra-fine Cratex abrasive, blah, blah, blah. Since I can't ride for squat, I take out my frustrations on my poor bike by messing with it all the time........

Jon

[copemech]

Jon, while standing there last week holding my one and only fork spring in my hand while changing fork oil after a year on the latest bike,I thought about you. Polishing the springs to reduce drag and all that stuff. I looked at the spring, looked at the old oil full of metal, and said to myself, well I guess I don't need to call Jon to find out how to polish these things, DUNK, into the fresh oil it went!

I am funny in a way, as Yes I do tinker as time permits, and yes everything must work properly for the most part ur it gets under my skin. But I have found that the outcome of a given trial for me muchly depends upon which balls I wear that day!

Big balls, little balls, brass balls, titanium balls, ali balls, tungston balls and the list goes on----! I usually start out on the lightweight ali balls, the green ones, and by the end of the day I may either have the big brass ones on, or could be the little blue ones?

BTW, you need to make a point to ride Steves 250 pro at the Sooner Cup. Sweet!

[jse]

Jon, while standing there last week holding my one and only fork spring in my hand while changing fork oil after a year on the latest bike,I thought about you. Polishing the springs to reduce drag and all that stuff. I looked at the spring, looked at the old oil full of metal, and said to myself, well I guess I don't need to call Jon to find out how to polish these things, DUNK, into the fresh oil it went!

I am funny in a way, as Yes I do tinker as time permits, and yes everything must work properly for the most part ur it gets under my skin. But I have found that the outcome of a given trial for me muchly depends upon which balls I wear that day!

Big balls, little balls, brass balls, titanium balls, ali balls, tungston balls and the list goes on----! I usually start out on the lightweight ali balls, the green ones, and by the end of the day I may either have the big brass ones on, or could be the little blue ones?

BTW, you need to make a point to ride Steves 250 pro at the Sooner Cup. Sweet!

Dear Sensitive Tush,

How very sweet of you to think of me when looking at an oily fork spring......

I agree, I don't think any rider needs to do all the stuff the way I do. Just following regular maintenance guidelines would keep the newer bikes in great shape. You changing fork oil once a year is probably more than a lot of riders do, and I bet a lot of bikes are sold to the second owner with the factory oil still in the forks.

Steve had his 250 out last Sunday when we were setting up sections. That's a really nice bike. It's hard to sell the U.S. rider on the choice of a 250 (over a 280 or 300 offered) as we tend to have the cowboy attitude that bigger is better and we want to supersize everything. When you ride it, you can really understand why the Euros like it so much. Very responsive and smooth and I would think a better choice for a lot of riders whose ego overshadows their talent and who buy a 300 and then want to tame it down. The 300 is great for a lower class rider who rides Colorado and Donner now and then, you can't beat them for high altitude work.

Jon