The Fred G. Sanford Fleet (Next Engine)

I keep wondering how I could do it, but I have the idea of using a wide belt, toothed variety with a toothed roller one end and a (possibly larger diameter) plain one on the other with the plain face of the belt in contact over a longer stretch of tyre than a roller can touch.

I got the idea of increase area from a picture I saw once of a complete minimoto mounted on the back of a pedal quad and driving a wheel. The minimoto wheel is lots bigger than a normal roller and has a nice sticky rubber tyre.
 
Another thought was to have an open cell foam or other porous material idler roller before the drive roller to soak or fling excess water off the tyre.
 
That's a very intriguing concept, Ludwig. I had a couple of similar ideas, but haven't tried anything in that vein yet. The lack of available space and dislike of riding in the rain has put it in the "maybe later" pile. :) I may have to give it a bit more consideration in light of all the rain we've had lately.
 
I know that trail riding with V-brakes using the rims surfaces as I exit crossing a small creek I have to be careful that I dry the brakes. Speed has to be slower not knowing the trail for safety.

For power to the wheels I have 1 chain and 2 belts. I have had a problem with either one or both v-belts if deep enough or splashes high enough. The idea of a back idler pulley I use on 1 belt to tension, but something to dry the belt give pause to think about.

It was 3 belt system, changed to 2 belts and a short piece of chain. A small 1.7 inch pulley was worthless trying to not have it slip, chain and two gears replaced it.

I wonder if the cogged belt I use with a less porous belt material actually drys off its surface quicker than the other belt I use. I could not get in that same style and material, because a length to fit in 1 inch increments did not fit with all the adjustment of my back idler.

MT
 
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I know how tricky those brake pads can be, MT. Thanks for the concern!

Whether wet or dry, these brakes are very abrupt. The "careful how hard you pull them" kind.

On my other FD BMX, the old style calipers slip a little in the rain and are much slower to come to a complete stop. Even with the handles and cables adjusted well, it doesn't hold a candle to the stopping power on the Mongrel.
 
There have been a few positive drive "rain" rollers on the forum in the past. They are of grit composition. On my Lifan/Mongoose I used a waterproof 60grit sanding belt contact cemented to an oak roller and well sealed with polyurethane. It drove the bike no matter the amount of water it encountered. Tire wear was acceptable when wet, but not so when dry. It was used as an emergency drive if caught in rain far from home. I used to take trips of 100+ miles on this bike and didnt like the idea of waiting for things to dry out. As the roller could be changed in under a minute, this was very practical. Im not a fan of riding in the rain either, but as showers are a fact of life in the South, I had to come up with something. Waynez made a drive roller from a grinding wheel that couldnt be stopped, but tire wear was an issue as might be expected.
I have been wondering if the Rustolem Never Wet or what ever it is would work. It might keep the tire/roller totally dry if their hype is true. It only takes a minute amount of water to slip a roller.
 
Curt, The purple bike has V brakes- and the blue one has the typical semicircle caliper. Both run the same size pads.

CB2, I did make a drive roller from a peg wrapped in vacuum belt rubber and interlocked/sealed (reverse wound) with duct tape. It worked a little better than the unwrapped grooved pegs, but not as well as I expected. I'm well read on the many drive wheels to be found around here, so I should be able to come up with something decent. Thanks for the tip! Never heard of the Rustoleum stuff before, but I'll definitely look into it.

Still, I find it more cumbersome to stop and change drive wheels than to just raise the motor and pedal the gears. It works pretty well for the time being. With the gear system and the motor raised, I get out of the rain fairly quickly.

Thank you all for your helpful suggestions. I read and consider every one. Also, Curt is sending me his clutch handle design pics. I always have an eye and ear open for good ideas. :)
 
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The scissors lift is an easy fab and clutches like a motorcycle at the handle bar with a hand brake lever. Mine easily lifts a 23lb engine with quite a bit of spring down pressure. Might have a look at this design also.
 
I'm really glad I decided to build a second chainsaw bike. This one became my daily driver for the last couple days while I was doing repairs on the other. You never know when you're going to need a backup.

Much like speakers, they work best just before something goes wrong. Funny because it's not funny. :D
 
Update: I installed a speedometer today. Same "bottom shelf" model as the other bike. The first one I purchased today didn't come with a battery in the packaging, so I had to return it for another. That's always fun. I could have just used the same brain for both rigs, but I wanted the battery I paid for.

All that aside, I've traveled about a half mile with it so far tonight. Even with the frequent stop signs, I managed a top speed of 25mph on the short trip. I've gotten so used to having one, I figured it was about time.

Next bolt on: a spiffy new mirror. Now that I'm riding this bike more, I can justify the expenses.
 
Took the first distance ride today. Went 6 miles (3 each way) on one saw tank worth of mix. I did bring the weed whacker reserve along, just in case it needed more.

Also, I managed a top speed of 30.4mph. That's not much of an increase over the blue bike, but the acceleration and torque are much improved. I even did a little bit of off road riding on it, just for giggles. Not very rough terrain, and not for very long- just enough to test the ruggedness of my mounting system and front fork. Took everything I could throw at it like a champ.

Some young women Cagers in a Jeep decided it was hilarious to play chicken in my lane, and nearly ran me into the back of a parked car. Laughing the whole time! WHO DOES THAT? I was riding on the shoulder in the right lane, and here they come, doing at least 30mph in a 25, straight over the center line and directly at me; head on. Luckily, I've been on two wheels a long time and constructed highly maneuverable bikes. I nearly met Hendrix today.

Other than that, my ride was excellent. A lot of people clapped or cheered at me, and most folks generally do get a kick out of these little contraptions when they see them. That always gives me a smile. :D

cvlt1
 
Had one case/motor mount bolt come loose ever so slightly after my various tests. Only noticed today after a pre-ride inspection. I gave that bolt a good shot of loctite, and drilled the slot in the bracket to accommodate another hole already existing in the case, an inch below the other. (Technically, these would be where the saw handle once attached near the clutch.) That added a bit of stability to the mount, and gives more locked threads to help it stay that way.

Definitely an underestimation in the original design. That was obviously the weakest point. Under all that pressure and vibration, it was only a matter of time. No idea why I didn't do two bolts from the beginning. I guess something was bound to slip by the goalie on this bike, too.

Took a short test ride on it after the loctite set up, and it stayed nice and solid. Of course, it took 6 miles of hard street and off road riding to loosen it up in the prior configuration. More testing will need to be done, but the problem seems to be solved at press time.

One more potential disaster averted by a ride checkup.
 
Looks like it worked! The bolts haven't moved at all after this morning's ride, but I'll keep an eye on them for a couple more days. Hopefully done wrenching on both bikes now. :)
 
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Had one of the two bolts holding the motor mount to the dropout holes come loose today. I removed the back tire and replaced the entire bolt, because I noticed it had bent a little. This has been in the back of my mind a while, because I had a feeling its small threads wouldn't take to the workload well. It was a five minute job well worth doing.

I replaced it with a bolt with larger threads, double nutted down tightly. Immediately, I noticed less vibration.

The tensioner bolt through the slot and motor mount on the other side was also in need of some attention. It had started to bend slightly as well, and only a matter of time before it snapped. I also replaced that one- with a larger black hardened bolt and two new nuts. Rides nicely tonight since these mods. I haven't noticed anything loose during the shake test afterward, so I think we're good to go. Very happy with the upkeep. Anything that has gone wrong has been very minor and easily fixable, and there really haven't been many issues. I wouldn't trade my chainsaw bikes for a shed full of kit bikes... :)

Moral: One pesky bolt can make a lot of trouble, if left unattended. Another win for bike checkups.
 
Dark days... A dear friend of many years, fellow musician, and two wheel enthusiast was taken from us on his Harley last week. He was chasing down thieves who had just stolen his brother's car at the time... He was a good man and a wonderful father, gone too soon. Proud to call Jake Rameau brother. Family isn't always blood. To know him was to love him.
We local musicians have banded together to put on a festival in his honor and for his family's benefit, and many more have stepped up to the plate and offered their help and time with stickers, T-shirts, and other donations to the cause. His tribute is truly fitting of the man.

This is how the bike's doing:
I've been doing a lot of riding lately, making arrangements for and attending memorials. Locked up the back wheel bearing yesterday. Seems the cassette gradually tightened the cone. 30mph for that many miles will do that sometimes. I had a spare steel 20" rim handy, so it got repaired immediately. It had just gotten to about 75 (documented) miles. Not surprising at all. I used Diesel (#1) for a couple rides last night while it was down, but both are running fine this morning.
 
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I finally located another 7 speed cassette on a 20" rim, to replace the original. Luckily, the new one is of much better quality than the last. I'll take shimano gears over mongoose all day. Using gears make drag starting much easier, along with the obvious benefits when under pedal power. A single speed would do, but chain alignment and the aforementioned positives were obviously in favor of a cassette.

I packed some white lithium grease into the bearings before installation and will keep a close eye on it. Rolled easily and true, even in the bone dry condition I received it in; so it should give me more than the 80-some miles I got from the stock rim. I'd loosen it enough to roll, and it would freeze. We had this struggle for a couple days, before I finally gave up the ghost on it.

Took a few short test runs, and the bike was great. No more death rattle in the rear or fear of bearings locking up at speed. Top speed is improved by a few 1/10ths-mph, but could have been a favorable wind. The important thing is that nothing was lost from safety, torque, or speed. The mean machine mongrel is back to normal, and I think it should stay that way for quite a while.

brnot
 
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Update: The new top speed is 32.8 mph, and the bike is running better than ever. Haven't had any issues with it since I replaced the back rim.
I did replace an engine support bracket (that used to be a reflector mount), with some thicker plate steel- bent at the same angles with the same mount holes. That was just for insurance, really. Nothing was structurally wrong with it as it was. Makes me feel safer, so it's worth doing.
 
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