ridgrunr

Yup the GG's were 236 cc through 1995. In 1996 they went up to 256 cc and they started calling them 270 in 1997 even though they were only 256. 249 cc is what Fantic used in their 250's

I don't claim to be any sort of fuel engineer, but there is an interesting article in my new Cycle World mag that came in the mail yesterday comparing carbs vrs EFI and the merits of both. Yes EFI does inject instant fuel into the cylinder on demand, but the problem with EFI is that that the fuel that it injects directly into the cylinder is still very much in large droplet form and not the small molecule form needed for really efficient combustion. This is called "cracking". So what basically happens in EFI systems is that part of the fuel is never burned, because the droplets are so big, then the piston rings pull that raw unburned fuel down into the crank. Over time what this does in a 4 stoke engine is to slowly dilute the oil with gas, reducing it's ability to lubricate, while also significantly raising the volume in the crank/transmission with gas diluted oil. This isn't a good thing. So maybe EFI is not the cure all in a Trials application unless they can figure out how to put in a catalyst of some sort to better "crack" the fuel mixture which will also add to the complexity and weight of the system. The new carbs being designed today are becoming more efficient at breaking those fuel droplets down so they can be more easily and efficiently burned. In small displacement low RPM applications like Trials motors, this is a prime directive for them to run decently. Maybe they'll make them easier to start too. The key I guess is in finding and using the right carb for the application. We'll just have to wait and see if anyone figures it out.

If I remember right, the JT models (JTR and JTX) were developed for GAS GAS by Jordi Tarres, hence the JT nomenclature. I think that started in about 1993. In 1998 Tarres moved on and the models became TXT. The main difference is that the JTX (and JTR models before them) had plastic fuel tanks. When the TXT came out in 98 it sported a new frame and an Aluminum fuel tank and new black anodized front forks. They were gold before that. The engines are very similar from the 91 with mostly minor changes but they got better as they refined the design. They went from 250 through 1996 to 270 through 1999 and 280 in 2000. They changed the frames again in 2000 when they got rid of the steel rear sub frame, and in 2001 GG changed the front fork. In 2002 they went to the PRO, however the TXT 280 was still offered for a couple of years. Prior to the PRO, The TXT models were the best of the bunch. I think the 1999-2001 TXT321 may be one of the best Trials bikes ever built. You can see how the bikes changed in looks here by clicking on the photos of the bikes on my web page here: http://www.geocities.com/utahtrials Hope this helps.

Here in Utah we have a cross country trail called the Five miles of Hell http://www.geocities.com/utahtrials/5moh/5moh.html . Very intense single track trail that requires that we carry extra fuel for the Trials bikes. We've tried everything. We discovered early on that the tanks that replace the number plate or headlight are not a good idea as they really throw off the front end balance. We had a lot of over the bars experiences with them. After all the whole idea here is to be able to let the trials bike do what it does best, and you don't want to screw that up by messing with the bike's balance. What we finally came on was 2 liter pop bottles, Coke, Pepsi, etc. You can put two of them in a back pack comfortably, and still have room for you camel back liquid and lunch. The things don't leak and are super tough. I guess you could break them as you could anything in the right fall, but we've had guys fall on them over the years and I've never heard of anyone breaking one. They are air tight too, and don't leak. They also have a fairly small opening that can easily be filled up and works well for pouring into the gas tank. All day long, as you get more tired, your pack gets lighter too. So if you carry two, you have almost three times the range that you normally would. They weigh next to nothing empty and are disposable (plus you get to drink whatever was in there first), so after you empty one, it can be crushed, taking up even less room in the pack. Then when you are through with the ride you just throw them away in the nearest trash can. Leave the lid off when you throw them away so the fumes don't build up in them. One word of caution. Make sure you mark them "GAS"! We had a really thirsty rider one year who thought he'd take a swig out of a buddy's bottle of pop. You guessed it, he got a mouthful of premix! Then he was thirsty and sick!

That's it! Can't understand a word there, but great pics with terrific detail. If you click on those small pics at the bottom they enlarge greatly. Terrific pics of the carb layout and underside too. Thanks for helping me find them again!

Can't find it there.

These are the pics that have me drooling over the Rev 4T. I stumbled on them somewhere in the net, but forgot to bookmark the page and can't find it again. The originals are large, high resolution pics. Terrific detail. These are toned way down to post here. Anyone know where these came from so I can find it again? Thanks.

Try the Maxima Lite transmission fluid, 75 wt. We've used it in all our Gassers and it really helped the clutch drag.

Thanks for the link betarev-3125! I'd seen the clip of the 4RT and Saunders on the 4T in the section before, but not the clip of him playing on that bank. Love the sound of the Rev 4T! It sounds like the RPM's can drop down to almost nothing, then run right up again with no bog. That would be terrific if that's the case. Maybe they have that CV carb figured out and dialed in? It's not even very loud when he's getting hard on the throttle. I sure like how un-poppy it sounds. Thanks again.

Sorry Lane, I said MOST guys don't follow what the national or world guys are doing or care what they ride. I'm not most guys. But, I don't buy anything just because some top rider might ride one. They mostly follow the money. See I know Mark personally, have ridden with him, and have taken a trials school from him and Tommi Avahla, so I know what he can do. I watched Mark and that 321 work for two days and he prooved to me what it could do. If I remember right, Aaron was on a Techno. Mark on the 321. The 321 looked easier to ride, so I bought the 321 based on what I saw, not what I was told. I won't buy a Beta Rev 4T or anything else till I'm pretty sure of what it is either, but so far, I like what I see. Time and rersearch will tell.

I sold my '99 GAS GAS 321 a couple of weeks ago. It gave me seven years of outstanding service. I bought the bike after watching Mark Manniko ride one at the Temecula National. I was in love ...with the bike...you gutter heads! Anyway it's been a long time since a bike has caught my attention like that 321. That's why I kept riding it for seven years, it's was a terrific bike. Then all the fuss started about the Sherco 320 and now the new Beta Rev 4T. I began wading through those 25+ pages about the Beta, then I saw the pics. Man, I'm lusting again. Don't know why, never really considered a thumper, but something about the way it looks just sitting there. Thing looks like it was poured rather than built, sort of like liquid mercury. I know EFI is all the rage, but if they can make that CV carb work...so that you can actually start and ride the thing.... Funny, I never felt this way about the Mont 4RT. There are a few of them in the club and I've watched them work, but have been sort of...ho hum on them. It just didn't light my candle, but something about that Rev 4T. The only Beta I've ever owned was a '90 Zero. Very ahead of it's time. Ok bike. Hated trying to get to the carb, and that left hand kick which they fixed (IMHO) on the REV 4T . Fortunately, due to a job change and a TDY move for a year, I won't be buying for awhile, but I'll be watching closely so I can see how this pans out, and who knows what the rumored 350 GAS GAS 4T might look like...that's an unknown. So keep the info coming, so I can figure out whether or not to get involved in another long term relationship again after I get the move situated. Thanks .

You know, we've been batting around this "why no US world contenders" for ever, and no one seems willing to admit the reason why the sport in the U.S. doesn't gravitate that way. I may have part of the reason for you...but you aren't going to like it. The truth is that the majority of the trials riders in the U.S., who actually compete in local trials, don't really care much what's happening in the sport beyond the club they ride with. Prime example...look at standardized classes and rules. I've fought that battle for fifteen years. Doesn't happen...and won't. And those folks who ride trials bikes for fun, or trail riding, who don't compete with a local club, don't care...at all. Basically it boils down to the fact that in the U.S. trials is a local participant sport. It's not a spectator sport and it's not done outside of the club they are affiliated with. Without gigantic numbers of spectators there will never be enough money involved to make it worthwhile to pursue. We don't have indoor trials such as Sheffield where folks can sit in a warm area and watch the world's best do their thing. That's what makes NASCAR such a draw. People can sit in one spot and see the entire race. People are basically lazy. If they can't sit in their seat with a hot dog and a beer, along with ten thousand other screaming fans, what's the point? The vastness of the country is part of the problem. To contend the National circuit, a rider would have to drive twenty thousand miles or more on his own dime. Very few riders are going to do that, and not for long. The few that do are the "hard core" enthusiasts, but if you'll notice, they are usually the same group year after year and that group is dwindling. Ten years ago we had a dozen riders in our club who rode some of the nationals, and a gal who even rode world events. None do today. Most of those riders who did don't even ride locally any more. You mentioned gymnastics and ice skating. Both are venues where a spectator can sit in a nice seat, indoors and watch the entire competition. Most all high schools and all colleges have gymnastics programs. Again, spectators can sit in relative comfort and enjoy the event. You'll never see that at Trials. I have chased world riders all over Donner, and National riders all over Lucerne Valley, Temecula and Flagstaff, but I only did it a few times, when I was younger. At 52 it's just too much damn work. Then when you do traipse all over the country side from section to section, the sections are so spread out that you often miss most of the really spectacular rides. Then there's the the two to three DAY drive, r more, just to get to the event and that much back. Heck it's a three to four hour one way drive for me to get to one of our local club meets, then I get to drive it again, alone, in the dark to get back home. I don't know about the other U.S. clubs, but in our club there is almost no interest, for what is happening in either the Nationals or the World scene. Nobody knows who is #1, #2 or who is riding what this year. Fact of the matter is, they pretty much don't care. When it come to trials here, riders want to show up, ride the meet and get home in time to watch the JAZZ play on TV. Yes the guys who ride locally love the sport, but mostly because they are motorcycle nuts and trials is a sport they can do on a motorcycle, not get killed...in most cases (but that's another thread)...and get up and go to work on Monday. So to most of the trials community in the U.S., Trials is a way to spend a day, just like if they were going out to spend a day fishing or pheasant hunting, and most of them could care less who's fishing or hunting in New England much less England. Sorry this sounds so negative. I told you that you wouldn't like it, but truth is sometimes like that...sorry.

I just sold my '99 GG 321. That dude competed in a Trials every month for over six years, plus unknown numbers of practice sessions and trail rides. It carried me across the 5 Miles of Hell every year with never a burble, and believe me that's a place you don't want a break down. Only a UH-1 would be able to get a broken bike out of there. It wasn't perfect, but other than tires and chains, and brake pads,the only thing I ever replaced was a set of piston rings, and it didn't need them. It still had the original factory fork seals and they had never leaked a drop...the original rear fender. Yes I'm meticulous on my maintenance, but it was about as solid a machine as I've ever owned. It never broke down and never left me stranded...ever. Not once. It was a great machine. It's been my experience that most all of the modern bikes a good reliable mounts, and I doubt a guy could go very far wrong with any of them. I've also found that the guys who do have problems with their bikes are the guys who flog the crap our of their machines, but NEVER do anything to maintain them. Then when they break down, which any one can do if they are abused, they bitch about what a terrible bike it was, when the bike usually wasn't at fault. Can there be bad bikes and bad designs? Yes. I think the upside down forks was a bad design because the most vunerable part was down where the rocks could get to them, then the fender mounts were mostly garbage, I think Beta's set up was the best. Fantic's hoizontal radiator wasn't a great idea either, but other than than my 94 KRoo was bullet proof. Are the GG Pro's as lasting as my 321? I don't know, I've never owned one, but if GAS GAS does actually build a 350cc four stroke push rod engined Trials bike, with EFI and it looks like a decent unit, I'll buy one.

Yeah I just stumbled on that pic which is the one they'll use in their enduro. That's from an old article from last March. A push rod valve engine would be way shorter especially if it was a flat head motor which a push rod engine could easily be.

Might look something like this?

The '70's CX500 Honda's had push rod motors. They would rev to the moon, and were a lot more powerful than their 500cc size would seem. Smooth too. The current Honda TRX model quads all have push rod engines too. Super low profile cylinder for low center of gravity...which is better no matter what Beta tries to tell us. So a push rod 4T GG may be just the ticket, less complicated too as there is no cam chains to deal with. Easy valve adjusts too. 350cc, EFI and the push rod motor. Now I'm drooling.

For that cable clutch, you can get a leverage enhancer. They are called an Easy Clutch. I put one on my 92 Fantic 307 and my 74 Yamaha TY250 and it made a huge difference. One finger clutch afterwards. They just go between the throttle and the cable, look like this: http://www.adarmx.co.uk/online_shop/index....target=d86.html

My 1985 Honda V65 Sabre has CV carbs. 4 of them, Keihins, on that V4 engine. I had a little mid range flat spot at about 4000 when I first got it, but shimmed the needles 2mm which fixed that. Thing still runs like new at 54,000 miles, with not a burble or hesitation up to an indicated 152 mph. I've had it from sea level to to the top of Mt Evans in Colorado at 14,000 ft. You could tell there was less air at 14,000 feet because even that 1100cc engine doesn't produce the power at 14,000 ft that it does at sea level, but it always runs perfect, and I've never opened up the carbs since I shimmed the needles. My 2006 Kawasaki Brute Force 650i quad also has CV carbs, two mikunis. It also runs perfectly from sea level to the 10,000 ft I've had it on the Paiute trail. I've never touched the jetting, it is stock. I live at 5300 ft MSL. So for my experience, the CV carbs have been terrific. I think they are better for all around performance than conventional throttle slide carbs, and start easier too. I do have to use the choke when cold, but as soon as the machines are running, I turn the choke off or they will start to burble. I guess the down side is the rubber CV boot. You have to be careful not to tear them when working on the carbs, as I've heard of some problems over the years with torn boots. Kawasaki seems to be the last hold out however on the CV carb thing on their quads. Almost every other brand has made or is making the transition to EFI, which is mostly EPA driven. My brother in law has EFI on his 2006 Can-Am 650. It's a tad faster than my Kawasaki, and uses about .5 gallons less gas through the 5.4 gallons of gas the quads hold, so the EFI is a probably little more efficient than the CV carbs, but not by much.

How will the crank get lubricated? I'm no engineer, but if they can lubricate the crank on a 4 stroke...

I've myself have been wondering lately about those spindly rear fenders hanging out there in the wind, not doing much except flop around when ever the terrain get really rough, and then get broken off if you even look at the mcross-eyed, especially when it's cold. How many rear fenders do you see at the meets that look like Frankenstein re-created them? I know the manufacturers probably like them cause they get $80-$100 or more a pop for them when they get broke, which happens a lot, but maybe it's time to look at a rear wheel hugging fender design that would move with the rear suspension and actually keep some mud off the machine and rider and not get broken so easily. And all this hype about four stroke motors. Heavy and unneeded complexity, plus a 4 stroke doesn't put out near the power that a same size 2 stroke can. If the real push is lower emissions, how about a fuel injected two stroke? Less complex than the 4 stroke and fuel injecting would help the machine run better across the entire rpm spectrum at any altitude at any attitude. Inject the fuel just as the piston passes the exhaust port on the compression stroke and not during the exhaust stroke. That's the problem with today's two strokes, they waste about half of their fuel by pushing raw gas out of the cylinder along with the exhaust on the exhaust stroke. I think they've got boat motors doing this now. It's time to put that technology to work on a trials bike.

All this talk about 4 stroke vrs 2 strokes and carbs vrs EFI. My head is spinning after reading these 23 pages. Seems like the topic has been beat to death, and everyone is mostly speculating, so let's spice up the discussion even further. I say bring on the EFI 2 strokes! Now we're talking! Even the EPA would have to like them!

I guess that could be a good argument for being wary of the first year out for anything. I remember the first 280 Pro and it's clutch problems. All had teething problems that were corrected in later models. One reason I am looking at the Sherco over the 4RT is that I am not a fan of Aluminum frames. I've done a lot of welding and when it comes to frames, I like steel. There are some videos floating around of the Beta 4 stroke vrs a 4RT that don't show much about the difference in the machines except that the Beta is quieter. Just looking at it, the 2007 4T looks like it's really well thought out. If they were able to keep that terrific Sherco clutch and have gotten it to start and runs reliably I think they'd have a winner. Here's an interesting video of the Sherco 4T. Seems like it works pretty neat here. Detail is pretty good, it's a big file, 20 megs. http://www.shercovictoria.com.au/sherco/pdfs/cabes1.wmv

I agree, different riders, different abilities. That's obvious from the start. The 4RT rider definitely has a heavy throttle hand. The riders on the Beta and the 4RT both took different lines on the loose up towards the end of the section with the Beta rider opting to go more inside at the bottom wide and staying out of the churned up mud there and at the corner at the top, so that may be one reason shy one appeared to hook up better. The one thing that really impressed me about the Beta was it was quieter and...they got rid of that stinking left hand kick starter!

Yup, most of us don't need the big bore bikes...for competition, but when it comes to trail riding they are the cat's meow, just put them in third and leave it there. The Five Miles of Hell in Utah is a perfect example. It takes three hours of solid riding to cross that monster. It's like three solid hours of Intermediate/Advanced section. With a small bore your shift foot gets tired in a hurry shifting all the time. So the bigger bore bikes with more torque are king there. I guess if we could afford to have half a dozen bikes, one for every occasion, that would be ideal, but as I can only afford one, I think I'll probably still look at a big bore to replace the GG 321 I just sold. I have been looking a lot at the 4T, but have had some very strong opinions about it's starting reliability, which doesn't seem to be the case with the 4RT. I know in the world of quads, almost everything has gone to EFI and it looks like that will have to be the case too for the future of 4 stroke trials bikes.

Hey Dixie, you mentioned that hard starting twice, so it must be a problem. That's typical of a lot of 4 stroke dirt bikes, which I imagine is why they have gone to electric start on most of them. How does the thing run once (if ever) you do get it running? Does it have that 4 stroke lag problem right off idle? It sounds like you gone to a 4RT. No starting or lag problems with the fuel injection?