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A 160 lb CRF230F?

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I seem to run across trials riders out in the field. As the evening came on and more beers were consumed they insisted I ride a Beta Evo 2T 250 and then a 4T 250 and 4T 300. Since I don't drink I took them up on these kind offers.

Try my CRF230F I said, heading off. They snickered. And belched.

I had been mountain biking that day so when I looked down I thought I was on my Giant Trance. These are adult size bikes but very, very light.

At one point I was on a trail that plunged downward like crazy. So I just turned the Evo in place by picking it up.

The quality and craftsmanship are superb. Many components are miniaturized beautifully. The radiator is the size of your hand.

When I twisted the throttle the 2T was a typical 2T: like riding a chainsaw I always say.

But the 4Ts..... ah so relaxing. The 250 felt like my CRF230F: wide power band and completely unstallable. The bike was quite happy to putt along at 3 mph over slickrock or cruise between trails at 30 mph. And extremely quiet. Uncanny.

The 300 reminded me I was on a Beta. Nothing like my Xtrainer but definitely a kick. The mapping switch mellows it back down to more like the 250.

I guess as a matter of principle trials riders don't bring their seats to meets, so I had to sort of pretend I was riding the Sport model with a seat:

http://www.americanbeta.com/content/evo-300-sport-4-stroke

Beta makes great seats. In this case it carries extra gas. And interestingly enough you can get these seats for a pretty good range of models and years.

So people will ask, what about 2 gallons of gas? What about only 6 inches of fork travel? How can I live without a magic button? Will it cruise at 60 on the freeway?

To me there is one answer to all these questions: 158.5 lbs dry.

Obviously that kind of weight does not come for free. The forks and swingarm are slender. You give up things, like hitting big bumps fast and range and top speed.

This is a trials bike that can be switched for slow technical trail riding. It is not a dual sport bike. It will go fast, but not rough and fast.

Light weight with quality is not cheap. Lots of people spend $7000 and up for lightweight mountain bikes. There is no gas tank on the base Evo: the fuel is inside the frame. That kind of fabrication does not come cheap.

A 300 4T Evo Sport is around $9000 with springs for your weight and a spark arrestor. Mostly handmade in Italy, including the engine.

I went back to my CRF230F and had to laugh. It was like riding a Harley. Electroglide....

158.5 lbs. Kind of sticks in my mind. Certainly not a replacement for my favorite bike, but a different flavor to enjoy on certain types of trails?

 

Edited by RedMesa
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Ah trials bikes are for trials riding or otherwise fun to put around the camp. I wouldn't ride one very far. Unless your really use to them the steep steering angle makes them somewhat dangerous for regular riding. 

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My CRF230F is great for "regular riding." For a trials/trails bike, I'm thinking steep 6 to 12 inch wide technical singletrack like game trails. SLOW riding where that steep steering angle is an asset not a liability.

Again, there is no free lunch. But I got a hint of possibilities for a different kind of riding.

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3 minutes ago, RedMesa said:

For a trials/trails bike, I'm thinking steep 6 to 12 inch wide technical singletrack like game trails. SLOW riding where that steep steering angle is an asset not a liability.

Lol, that's a harescramble course here. Between trees, on the gas in second/third gear on an MX bike. Trials bikes are for 3-4 foot ledge rock staircases, boulder and big log hopping type stuff. We have a couple dedicated trials bike areas in our local OHV park, pretty wild back in there. :smirk: 

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I did in fact try to ride a trials on a tight single track loop 50 mile ride. On the real tuff places it shined. Every other place all the bikes passed me. So any idea about riding one on any ride with all types riding. Best keep it close to the truck or where it is meant to ride.No less great bikes real fun to ride.

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19 hours ago, OLHILLBILLY said:

Lol, that's a harescramble course here. Between trees, on the gas in second/third gear on an MX bike. Trials bikes are for 3-4 foot ledge rock staircases, boulder and big log hopping type stuff. We have a couple dedicated trials bike areas in our local OHV park, pretty wild back in there. :smirk: 

I can ride these game and hiking trails on my CRF230F or AJP PR4. But not quietly, with minimal throttle, with minimal impact, leaving no trace, and minimal fatigue. Thus my interest in a 160 lb bike that moves like a ghost. The whole point is a different experience, not the same experience. 

On the other hand, I can't ride big obstacles on any bike so that is not a factor for me. A machine can only help so much and I don't have the skills. From what I've seen at trials meets, 2/3 of the participants can't do the big stuff either. They have the machine, they get better, but ultimately they lack the skills to progress to the next level.

BTR, given your style of rides what you say makes perfect sense. Since I mostly ride alone and slowly, not a consideration for me.

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I've also been on a quest for massive weight savings WITHOUT all the usual compromises. 160 lbs or even much less has been done by using small pit bike engines or 85cc two strokes and some bicycle components. These can be quite fun on the right trails but generally won't hang with your buddies on 250's/450's much of the time. Too little suspension travel,.. too skinny tires,.. marginal power

Trials bikes with seat kits are light and torquey but have the wrong steering geometry and ergo's for a lot of uses. As you pointed out, the short suspension travel, small brakes and frame stiffness are also an issue for rough terrain and high speeds. 

My criteria is that it must be something with good sand geometry for where I ride, quality long travel suspension and good brakes with ample tractable power for full size people. This rules out trials suspension and bicycle parts, skinny tires, and very small engines. The real world test is whether you can you ride with your regular buddies on your favorite trails and keep the same pace. 

My bored and stroked XR200 in a BBR frame with 18/21 wheels meets all these goals and comes in at 180 lbs. no gas but all other fluids. I can confirm that it is a very different riding experience. The positive difference is felt immediately and its effect grows rapidly as you learn to relax your grip and stop bracing for forces that just aren't there any more. Quite frankly it will make you feel and ride like you did 10-15 years ago! Everything about riding becomes easier and more fun. Within our riding group I have used 250 - 450 - 650 two and four stroke bikes and always rode about the same speed in relation to others. I still keep the same pace I always have but the physical effort is FAR less now. I also have less white knuckle situations and close calls. I can ride my way out of trouble that would have made me crash before.

My bike still has some meat on the bone,.. the frame is quite chunky and the tank is heavy. In a couple weeks I'll start documenting the build of my 2nd generation frame using better KTM components. The target will be 170-175 lbs all fluids except gas. That's with a 220-270 four stroke engine. I could easily hit 160 lbs. with a KTM150/200 or KDX200 air cooled two stroke engine but i just prefer a lightweight thumper. 

I think weight reduction could be the next big trend but it goes against the current trend of adding more complexity to bikes.  I feel someone needs to demonstrate a no compromise lightweight bike to show what is possible. I think KTM for instance will make what people ask for and they have all the existing parts to do it.

The problem is,.. people aren't convinced weight reduction matters much,... until you start talking 30-70 lbs less weight!! That's like removing the engine!

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Woodsryder, what else does your BBR XR200 have done to it for weight reduction, other than the frame, if you don't mind me asking? Forks, shock, intake, exhaust, wheels...

My main riding partner and I have been kicking around the idea of building our own bike (small task, I know) since we work in machine shops and can weld. He wants to design an engine, but I think that is way too ambitious to start out. What I'd like to do is take a CRF230 or XR200 as the power-plant, and build a new lightweight frame for it, use lightweight suspension parts (CR85 or similar forks/shock), and then machine any billet parts such as brake pedal, pegs, swing-arm parts, etc. for weight reduction while still keeping it durable and reliable.

I don't want an aluminum frame, solely because it's too bulky and makes it difficult to work on the carb/engine/exhaust. What I'd like to do is buy a frame or roller (CRF/XR) and make a sturdy jig for the new frame. The CRF230 dimensions and geometry is pretty good to begin with for my needs, other than possibly increasing the wheelbase like many on this forum have been doing recently.

The stock frame is mild steel, correct? If so, I'd use chromoly tubing with about half the wall thickness because it is much stronger. I'd like to make the footpegs and handlebar positions adjustable, and any other parts that may make the bike more versatile for different size riders.

Yes, this sounds like a big project, and I don't care if y'all shoot me down for it. I believe that it can be done if I make enough time for it. That "IF" is the biggest factor holding me back right now. I still need to do some more research on jig building and frame/suspension geometry right now. I'm even considering going to a linkage-less shock like KTM's PDS shock system to reduce weight and simplify it. However, this would take a lot more tuning time to get the proper spring rate and valving.

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Heres an old thread with most of the build details for my BBR but for some reason all the pics are gone. 

I got the weight down through careful parts selection but no billet parts or exotic metals. I used Honda, Yamaha, KTM and trials bike parts. There was a fair amount of fabricating involved to mate up the different brand components, extend swingarm, relocate the pegs, hand built 3.5 lb exhaust system etc,.. I think I weighed every tire and tube in the world to find the lightest.

A ground up bike/frame build is no trivial thing but I've done it before. In 2015 I built a prototype sport bike for the "ex" head stylist at Buell. It was a very difficult frame with curvy exposed tubing and 3D printed body parts. He is pursuing funding to start production. 

http://47moto.com/mosquito/ 

I'll be using the frame jig and tube bender I made for that project.

KTM and japanese mx bikes have always used 4130 frame tubing. Trail bikes like the 230 most likely use plain steel?

 

 

Edited by woodsryder
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1 hour ago, woodsryder said:

Heres an old thread with most of the build details for my BBR but for some reason all the pics are gone. 

I got the weight down through careful parts selection but no billet parts or exotic metals. I used Honda , Yamaha , KTM and trials bike parts. There was a fair amount of fabricating involved to mate up the different brand components, extend swingarm, relocate the pegs, hand built 3.5 lb exhaust system etc,.. I think I weighed every tire and tube in the world to find the lightest.

A ground up bike/frame build is no trivial thing but I've done it before. In 2015 I built a prototype sport bike for the "ex" head stylist at Buell. It was a very difficult frame with curvy exposed tubing and 3D printed body parts. He is pursuing funding to start production. 

http://47moto.com/mosquito/ 

I'll be using the frame jig and tube bender I made for that project.

KTM and japanese mx bikes have always used 4130 frame tubing. Trail bikes like the 230 most likely use plain steel?

 

 

That's a nice looking prototype bike...

So what's stopping you frame making a new frame and swing-arm for the XR200?

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16 minutes ago, mx4god said:

That's a nice looking prototype bike...

So what's stopping you frame making a new frame and swing-arm for the XR200?

Nothing right now finally,.. I did the BBR as a quick proof of concept bike to see if the component weight numbers I've been collecting would check out when all put together. Im happy with the weight results and was surprised that I stumbled on a steering geometry combination that works amazingly well.

Then life got busy and I couldn't do anything with it for years. I have my own business and also do special prototype projects as they come up. I then got sidetracked building a long travel Hayabusa powered buggy and started building a house in Florida all by myself. The house is half done and I'll be taking a break for 6 weeks starting the end of May.

I hope to get one or two frames built during that time.... unless something more fun comes up!

Edited by woodsryder

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My 251cc BBR framed bike (150f based engine) weighs 192 lbs with a full tank of fuel.
DLC coated race tech CR 85 forks
OHLNS CR85 rear shock. TAG trees.
The frame only weighs 4 lbs less than a 230f. (Less swing arm)
But that may be because it has a steel CR 85 subframe and uses no top of cylinder head/engine mount of any kind. (And no place to bolt one on)

My 2005 BBR bike compared to a stock 2005 230f:
No kick stand, lighter rims and wheel assembly's, (CR 85), lighter rim locks, aluminum trees, lighter tires, aluminum steering stem, lighter CR85 swing arm, lighter front disk brake rotor, with the lighter rear disk brake rotor, the whole rear bake assembly may be lighter than the 230f?, smaller fuel tank, aluminum bars have no crossbar, lighter seat, aluminum shifter and rear brake lever, lots of aluminum nuts and bolts in non critical applications, front fender has many slots for additional air flow to engine. (May be lighter?)
Smaller diameter axles and swing arm pivot bolt. Featherweight Flywheel (compared to a 230f) and then lightened as much as possible) no electric start, 5 speed transmission. Lighter piston, lighter cylinder head, (porting) lighter intake valve guide, (Shorter For Coe's MC-1 cam), one throttle cable, XR 200r carb is much lighter than the stock 230f carb. Lighter throttle housing, And like stated above, no top engine mount of any kind, Aluminum muffler.
But it has oversized kick start gears, a steel kicker shaft and a steel lever/arm, and while the foot pegs are much wider, both pegs and both brackets are heavy steel like the 230f.

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58 minutes ago, woodsryder said:

Nothing right now finally,.. I did the BBR as a quick proof of concept bike to see if the component weight numbers I've been collecting would check out when all put together. Im happy with the weight results and was surprised that I stumbled on a steering geometry combination that works amazingly well.

Then life got busy and I couldn't do anything with it for years. I have my own business and also do special prototype projects as they come up. I then got sidetracked building a long travel Hayabusa powered buggy and started building a house in Florida all by myself. The house is half done and I'll be taking a break for 6 weeks starting the end of May.

I hope to get one or two frames built during that time.... unless something more fun comes up!

And I thought I had large projects, haha... Well please post your info, pics, or videos if/when you make some more progress. I've only put a couple hours on my 230 so far, but can already feel the difference in weight compared to my 200 (close to 10 lbs. lighter than stock).

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1 hour ago, adnohguy said:

My 251cc BBR framed bike (150f based engine) weighs 192 lbs with a full tank of fuel. 

That's better than most,.. I've heard 195 lbs is average for the BBR's but most people add some blingy wheels or something that adds weight. Heck, you can add 1 1/2 lbs just with a fancy graphics kit!

Does yours use smaller wheels or an 18/21 combo?

 

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I found a Beta Evo Sport 300 4T at an irresistible price and not far away. First trail ride

https://goo.gl/photos/5Lod6TLXq56iAfST9

was in sandy badlands due to fire restrictions and travel. Over a hundred degrees and not really the best test but I wanted to give it a ride. 

It has a lot of throttle response and will go quite fast. I have not even tried the "power" setting of the CDI mapping switch. Louder than I remembered the other one being. Good bit of vibration. Fan blows hot air right on the rider when seated. 

The seat is.... Minimalist. I am going to try to build a custom seat out of thermoplastic and working with a local upholstery shop.

Got 28 mpg in mostly first and second, so the range will be about 50 miles.

Other than the seat, I think the bike will be comfortable and fun for up to 4 hr technical trail rides, mostly in first and second gear. One of its functions will be to remind me what a comfortable cruiser the CRF230F is ;) Also I will be trying some trials riding.  

 

Edited by RedMesa

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That is going to be such a fun bike once the trails are open again. Looks like a powered MTB. And now you have a upholstery project to keep you entertained until they let us ride again. I can imagine it was well out of it's element out there in the sand.

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Looks like fun. Wonder how they hold up? Must be using downhill MTB parts.

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As I understand it, the components are all motorcycle specific design sourced. Unfortunately, production is on hold awaiting investment financing. Apparently though, some  bikes have been made and are out there.

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I love seeing these variants! We are moving slowly towards a better trail bike but we are not there yet.

The manufacturers give us only oversized high strung race bikes, or recreational pigs with drum brakes and toylike suspension. At least now people are probing in different directions. Ive been watching the FX bikes from the beginning but to me, they still fall short in some ways. They used to have bicycle forks, wheels stc,.. and weigh 125 lbs. now they use trials forks and M/C parts but now weigh 160 lbs. My criticism now is the short travel suspension, narrow tires and even with the optional 190 engine, they only have four speeds with close ratios.

My criteria has always been that the bike must be able to hang with your regular riding buddies on typical trails. The FX bikes are best when ridden with other FX bikes on trails suited to them. They may even be more fun and capable on just the right hardpack singletrack, but get them out in some deep sand with the skinny tires and small motors, or in terrain that needs full suspension travel and your buddies will all be waiting for you. Face it,.. the group is not going to stay on trails where their bikes suffer and yours excels. 

I think the Freeride also fails this test with its trials oriented steering, modest suspension and 205 +gas riding weight. The Beta crosstrainer can hang with regular bikes with better geometry, suspension and reduced size and height, but it weighs as much as a regular bike. I think all these attempts are converging on the sweet spot I have been enjoying for several years with my upsized BBR200. A bike in the 180lb range is light enough to shock you when first ridden. The bored/stroked 200 has some real grunt and the 6 speed wide ratio gives it some legs for real versatility. The compact size makes it nimble while the full travel and stable geometry makes it deep sand friendly.

At this point in time I think the Freeride is the closest to my ideal bike but with major flaws. It has some real nice light and strong components and suspension that can be upgraded enough. The reduced size would benefit many riders too. In my opinion they missed the mark by not using a tuned for torque 200 exc based engine which would have easily dropped another 10 lbs over the 250 engine. Also the trials inspired steering geometry is less than ideal for many areas that favor more stability. A simple light four stroke would be the ultimate upgrade.

The move away from full on race bikes for everyone,...  to competent lighter playbikes has begun. Most people would have more fun with less effort, and ride better if the bikes were rider friendly and less like last years supercross winner.

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