XR100/RM80 Conversion Pit Bike Build On A Budget – Part 5

Time to start putting the big stuff back on to make this a rolling chassis… So far I really don’t have as many hours in this project as I anticipated. Although, it’s far from being over. To see what I finished in my previous article of this build, go to Part 4 Here.

First, we’ll put the rear shock and swing-arm back on…

RM80 Shock and Swing-arm


Then comes the front-end and wheels to make it a rolling chassis with an engine.

It is going to look ugly for a while…

Now I want to share with you some of the issues I’ve come across on this conversion build, and try to solve them so everything properly functions. First of all, the brake pedal has some interference with the kick-starter shaft. This is probably the easiest to solve, as you won’t need to make your own pedal like other builders did with the CR85 chassis. The brake pedal still operates, but you can just grind a small notch in it to make clearance for the shaft.

Brake pedal hitting kick starter shaft.

Next problem, which I’m still trying to figure out, is the airbox/intake. I want to make everything look as close to stock as possible, so I’m still using the XR100 intake boot from the carburetor to the cylinder head. The RM85 airbox outlet for the intake boot is on the wrong side of the shock, and I can’t flip the intake boot because there is no clearance as it sits. I may have to modify/chop a section of the airbox out. Right now I have a pod filter on it right now for testing purposes.

Airbox outlet on wrong side, and no clearance to flip the intake boot…

And for the part you may or may not have been waiting for…… Since I do not like the look of the out-dated RM80 body-work, I decided to go the extra mile and convert it to the newer and much better looking RM85 styling. I did research on what parts are the same and to see if anyone else has converted theirs. I found out the front fender is about the only bolt-on for the newer plastic, and I couldn’t find anyone else that had done the conversion. That’s too bad… Because you’re going to learn how! If you’re already doing the XR100 conversion, the process to convert to RM85 plastics isn’t any harder than what you’re already doing; just takes a little patience and fitting of parts.

I don’t know how many hours I spent trying to figure out what I need to do, but I think it will be well worth it. This was because the 80 vs. the 85 parts looked the exact same, so I said screw it and ordered a tank, shroud, seat, side panels, and airbox off of eBay  After setting the tank and seat on the dirt bike, there were no mounts/holes for the rear of the seat to bolt to… So I took another look at an RM85 frame, and it finally dawned on me. Doh! There’s a post on the frame under the rear of the seat where it and the side panels bolt too! Since I’ve already done a lot of modifications to the frame, I figured this would be fairly simple. On the flip side, I made yet another mistake. The last year of the RM80 was 2001, but it got upgraded side panels, as well as fenders in 2000, although the tank/shroud remained the same. I didn’t know this when I ordered a seat from an ’01 RM80, but it doesn’t fit on the 2002 and newer RM85’s, nor a 1999 and older. This is a mistake that cost me, but now I know that they don’t match.

I used some scrap steel to make this. It’s about 7 gauge material, so it’s strong enough to hold up your rear-end. I just measured the distance between the seat mounts, cut, welded, and kept grinding the post until it fit, and the plastic bar touched the frame (see pic). I’ll drill the holes after I find out exactly where it’s going to be welded onto the frame.

Rear Seat Post

That’s all for today. I just ordered the last of the plastics I need for the conversion, so the next update will be making everything fit together, and possibly the start of a custom exhaust… I’m hoping to have this bike 100% ride-able with just two more updates, so don’t forgot to come back and check soon!

-Tom Stark

XR100/RM80 Conversion Pit Bike Build On A Budget – Part 4

This ultimate pit bike build is slowly but surely coming together… If you read the Previous Article on RM80/XR100 conversion bike, you’ll see that I had just welded up the frame cradle and set the actual XR100 engine in to make sure it fits. There are still some important features I have to add to the frame, but other than that, it’s just a lot of odds and ends to get the bike up and running.

The cradle is done, and the engine can plop right in, but first we need to strengthen it up. Why do we have to take the time to add more structure to it? This is an adults pit bike, and the whole reason we do these conversions is to make it a better performing bike that’s built to last! If it isn’t any stronger than the XR100 chassis it’s just going to break going over jumps, and may result in an injury for the rider.

I added a ‘gusset’ to the front of the frame cradle/down tube. I saw this on most of the other pit bike conversions, so I figured it was important to have. I just used a scrap plate of metal and cut it down to fit over the square tubing. (Don’t worry, I will be cleaning up my welds and the rest of the frame before it’s completely finished). Always remember to clean/grind the metal that you’re going to weld, otherwise it won’t get any penetration and will crack under load.

Frame Cradle Gusset

Next thing is to add/replace the upper frame tube that goes right over the engine. The original one was already cut off when I got the bike, so I just had to bend a piece of tubing and weld it in there. Since I didn’t have a great bender it took a while to get the piece to fit, and even then there’s less clearance than I would like.

Top Frame Brace

This will be a lesson for you, and for my next build. Although I can probably bend it a little more, I will still probably be pulling the engine out to do any work on the top-end. If I really wanted to take the time, it’s not too late to adjust the mounting location for the engine. If I were to do it again, I would lean the engine more forward so it sits within a half inch of the down tube, and that alone might lower it enough to be able to remove the valve cover. Fortunately, the XR100 has such a simple layout that it’s just a few bolts and the engine is out.

Now That the engine cradle and mounts that I machined are all ready to go, it’s time to stick the actual engine back in and start routing electronics. There was just barely enough room in the frame above the cylinder head. Since this is a budget build, and I didn’t want to use the mounts off the XR100 frame, I cut up a couple pieces of scrap sheet metal, bent them, and then ground them until they just barely slipped through the rubber fittings. I put a small ‘hook’ on the ends of them to help keep them in place.

Mocking Up The Electronics

Once I got those bent and fitted, I had to make a spot for the ignition ground to bolt to. I’m as cheap as it gets, so I just took a nut that the ground bolt fit in, and welded it to the inside of a washer.

It’s cheap, and it works.

Now here’s how it looks with all the mounts welded up. Looks like the electronics are ready to go, so we can move on to installing the bigger components…

Everything fits and works. If I can do it on an RM80, anyone can do it on a CR80 with more room.

I know it may not “look” like much, but these are some of the key components of this conversion build that are important to know if you’re considering starting an awesome project like this. Look for the next article soon, as I’ll be putting on the suspension, wheels, and other parts that make it look more like a dirt bike. Not to mention the start of my own little conversion in itself…. I’ve already said too much, so stay tuned.

Part 5: RX100!

-Tom Stark

UClear Bluetooth Helmet Communicator Boomless HBC100 Review

When you hear “Helmet Communicator”, what comes to mind? Usually a large pair of headphones, a big boomed-mic that sticks out in front of your face, and wires dangling down to connect to whatever device you’re using. Fortunately for us, modern technology is increasing every year, and now the UClear Bluetooth Boom-less Helmet Communicator available to the public. It has so many unique features, and is “Military Technology”, so you know you’re not getting cheap Chinese junk. When I got asked to test out UClear’s HBC100 motorcycle communicator, I jumped on the opportunity because I love technology, and I figured YOU would want to see a real-life review on it. Now when going in to this, I was a little skeptical since I hadn’t dealt with helmet communicators before, and seeing that this was the world’s first “boom-less” system I didn’t know what to expect.

HBC100 Bluetooth Communicator

Talk On-The-Fly

That’s right, you can answer, talk, and even call people on your cell phone while riding, without even having to touch it! It’s easy to use, even if you’re listening to music through your phone. Just pause the music and hold the volume buttons down for a couple seconds to activate the voice command. The capabilities are whatever your phone supports!

No More Boom-Stick!

Uclear’s HBC100 is the first boom-less helmet communicator on the market. What’s better about not having a boom? For one, it takes up much less space in your helmet (especially if you have a full-face), there’s nothing to hit your mouth on, and Uclear’s military technology helps cancel out wind-noise at well over 100MPH.

Bluetooth – The New Wireless

Do you remember the days of having umpteen cords just for a couple of speakers? Fortunately for you, those days are long gone… Bluetooth is the way to go now, and it’s easier than ever to use it. Just turn the communicator on, hold down the volume buttons for a few seconds, then turn your phone’s Bluetooth on and the HBC100 will show up on the available devices. Press ‘connect’ and you’re done! No more cords dangling down through your clothes that can get caught on things and ripped off. Once you’ve synced your phone, next time you just turn Bluetooth on and it will automatically sync when the communicator is turned on.

Sound Quality?

If you can’t hear the person on the other end of the conversation, what’s the point of having a communicator? Based on some outside variables (more on that in a bit), the Uclear HBC100 sound quality is surprisingly good. If you’re just having a conversation through via Bluetooth  it’s just as good as using your phone for you and the person on the other side. Wind noise was not an issue. Even going 70mph on a naked street bike, the wind was hardly noticeable. In fact, you can often hear the bike humming through the gears just as much as the wind.

Isn’t Wind A Factor?

Didn’t we just go over this? Yes and no. Yes, wind is always a factor. Does it affect the sound quality? No, not with the UClear. Where wind comes into play with a helmet communicator is how well the rider can hear. If you’re cruising down the freeway at 70mph or more with no wind protection, it’s going to be pretty hard to understand what the other person is saying. Or if you’re listening to music, it’s pretty much useless. That’s why it’s best to have a full-face helmet that is good at blocking wind noise. Not only will it be hard to have a conversation with the constant noise of wind rushing past your ears, but it’s just plain noisy and annoying. Unfortunately, I’m still using a cheaper motorcycle helmet that doesn’t offer many luxuries. If you’re going to be using a helmet communicator, just keep in mind that a quality helmet is just as important.

What’s Hot?

  • Boom-less microphone
  • Voice activation answering and calling
  • Stream music wireless through bluetooth
  • Rider intercom with other riders in your group
  • Boom-less Microphone with Active Noise Cancellation (effective to 147 mph)
  • Can sync with up to two devices simultaneously via bluetooth (e.g. mp3 player and phone)
  • Battery life (10-15 hours)

What’s Not?

  • Music isn’t the greatest quality because of wind noise
  • Glasses are more difficult to get on
  • Speaker velcro glue isn’t perfect

What Other Consumers Are Saying:

  • It doesn’t get better than this
  • Top bluetooth headset
  • Best Helmet Communicator Ever!
  • Great product for the price
  • No more wires!
  • An Impressive & Functional Product

Overall Impression…

If you go back-to-back with other helmet communicators in its price range, there isn’t much of a comparison as far as capability and quality. Bluetooth is the way to go, and it is very easy to use. I like the voice activation features, once again making it completely hands-free (unless you want to change the volume). It’s not perfect, but it mainly depends on how well your phone is capable of picking up your voice.

I often stream music while commuting on my bike, and I can go directly from music to answering my phone without touching anything (phone call supersedes music is a built-in feature). I have not tried the rider-to-rider intercom yet, but I’m sure it’s just as good or better than every other part of the system I’ve tried. And last, but not least, it’s a boom-less microphone that derives from military technology. For real, the absolute only cord is the one going from the speakers to the communication box, which is also on the helmet so they will never get tangled.

No matter what helmet communicator you get, wind noise will always be a factor. That’s why it’s good to consider a higher quality helmet that blocks out noise better than less-expensive helmets. If you already bought a helmet and don’t want to upgrade yet, there’s a couple other options for cancelling wind noise. The easiest way is sticking one of these Wind Stopper Skirts on your helmet. It’s cheap, and will make your conversations/riding experiences much more enjoyable.

One final thing I think I should add since I like to know every little detail about high-buck products before throwing my hard-earned money out there… If I could, I would only ride during the day. However, since I started working second shift, I do a lot of day and night riding, which forces me to keep a clear visor on my helmet. This is why I use sunglasses during the day, and even safety glasses at night if it’s warm enough. Since the HBC100 speakers are installed in the ear cavities of a motorcycle helmet, it makes putting glasses on a little bit tougher, depending on the size of them. I don’t have a problem riding with glass for an hour or so, but if I were to go on a road trip, it would get annoying and my ears would be sore after. Ultimately, if you’re like me and ride days and nights, the best option is to buy a helmet that has a built-in sun-shield. Yes, you’re going to pay more for one, especially if it offers good wind blocking, but if you want to be able to see and hear I believe it will be well worth the price.

As far as dirt biking goes with this wireless communicator, it mainly depends on how loud your bike is. I would not recommend using it for motocross racing, unless you just like listening to some tunes to keep you calm and have a safe place to keep your media player. On the flip side, if you’re on a trail ride with some friends, having the HBC100 can be very useful. If someone goes down and/or gets hurt, the sooner the others know about it the better (every minute counts, especially if you’re out in the mountains).

Technology is getting better and cheaper these days. Right now, this helmet communicator is hard to beat at its price. For more specs and reviews, or to Buy My UClear HBC Bluetooth HERE!

-Tom Stark