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The reliability and simplicity of a big single cylinder motorcycle is something I desire - more specifically I am drawn to the legendary and robust dual-sport XT/TT 500. I am all for the power to weight ratio of these workhorses, but I cannot seem to get my hands on a road-legal one in CANADA. I can, however, get my hands on the engine alone, and a deal of a used 1986 XT600! There is no urgency in my pursuit of the ever-alluding XT500 frame-with-ownership... but the idea of the ever-reliable 2-valve 500 single with mono shock rear suspension... a thumper of pure beauty. They are both conveniently dry sump to my understanding. The 1986 XT600 was even 2lbs lighter than the same year XT500 - according to my research. Would this conversion mean yet a lighter bike? I would plan on stripping the bike down, tricking the internals up, suspension, the works, and finishing it off as a sort of scrambler, inspired by the original XT500. It would be the bike and ride of my life. I hope to hear good things about how this venture could work. I am young and ambitious, so to fabricate or to not fabricate, your input would be appreciated. Cheers, Daw

I learned in diesel school about tolerances and Electronic Fuel Injection, and I am quoting what 3 other Thumper Talk members said to help better inform dirt bike riders what a good reliable 2 stroke dirt bike were to look like if fabricated to last longer. My goal is to one day be able to shred a two stroke dirt bike for thousands of miles on the original piston as I am not a racer. I know of some 2 strokes made that can shred more than 5 thousand miles without rebuilding it. I am interested in two stroke dirt bikes with EFI and I was just looking at what these people (I put their usernames as they can get credit for what they said) said on a post from 2019 here is the post name Video: KTM'S CARB VS TPI (TRANSFER PORT INJECTION) on thumper talk SmokeX said: It’s not that apparent to me. I love technology just like most everyone else. Who here wants to go back to a crab on their autos. Give us a game changing product that is as reliable as the one it’s replacing, and it will take off with out a few feeling the overwhelming need to boost a faulty product. 2strokenut replied to SmokeX: You're never going to get an EFI dirt bike to be as reliable as a carb'd one. You'll always have more failure points. No one on a 4t EFI bike wants to go back to a carb and it will be the same for 2-strokes very soon. Boertman84 replying to 2strokenut: Exactly, a 1979 cr250 has less failure points than a newcarb bike, no radiators or powervalve to fail. You see how that argument has no merit? If oil pumps and fuel pumps were failing at a high rate then you might have a valid point, but there is literally no evidence of this. Here is what I (Tchaikovsky) have to say: What I learned in diesel school is back before they had technology to help them build engines what they did was calculate the amount of metal they need by hand on paper and what happened was they would make an engine block with thicker walls than needed and other parts of the engine thicker than they needed. Now there is a good thing to this and I will let you know what that good thing is after I discuss what technology has done in the next paragraph. What I learned in diesel school about technology is the manufacturers who started getting access to technology to fabricate and construct “better” engines is they were able to build a engine which is lighter weight than back in 1979 when they didn’t have technology to fabricate and build the engine. I put the word “better” in parenthesis because they are not necessarily making better engines with technology than they did back in 1979. What technology allowed them to do is build the engine lighter because the technology showed them the tensile strength of the metal they were using and how to get closer to using a minimal amount of steel for a block wall or using a minimal amount of steel for the compression rings. (((this is what I think 2strokenut is referring to when he said “You're never going to get an EFI dirt bike to be as reliable as a carb'd one.”))) Sure the engine is lighter weight but is the engine really better for the customer who bought the bike? I say the answer to that question is NO, and the reason why is because the technology that they are using to build the bikes is allowing them to get closer to using the minimal wall thicknesses and minimal amounts of material. And what happens when you go towards the minimal wall thickness? The answer to that question is there is a higher chance of the wall breaking. What happens when you go towards the minimal thickness for compression rings? The answer to that question is there is a higher chance of the compression rings failing. – An Example I have on compression rings is --- I drained the oil one day on my 4 stroke 1991 Tecumseh 221cc engine which I put in my bmx bike for a homemade dirt bike and the next day I went to turn it on without oil and about 2-2 1/2 minutes later I rushed to turn it off when I realized I forgot to put oil in it. I put oil in it and it started up again and I have been running it since. I have taken apart quite a few other older 4 stroke engines like my 1991 engine and I see that back then the compression rings they used are much thicker than the compression rings they have put on engines made in more recent years like years after 2008 or so where technology has “helped”. So chances are if I had put a 2017 4 stroke engine in my bike with thinner compression rings my homemade dirt bike would not be running as if I had started up a engine with thin compression rings without oil the compression rings would fail much sooner than 2 or 2 ½ minutes or if they didn’t fail completely there would most likely be more damage done. But do you see my point on how thicker compression rings are probably the reason why I am still shredding? Who wants to drive a dirt bike that has a higher chance of breaking down because the manufacturers made it close to the minimal tolerances of the material? What I would like to see is a 2 stroke dirt bike made with EFI and made with thicker compression rings and thicker block walls (thicker block walls would make less of a chance of the block breaking if the connecting rod breaks and hits the wall and I have seen that happen on quite a few dirt bikes that me and my friends have repaired) and if any of you other mechanics can think of places were dirt bike parts could be improved? I get that the racers want to have lighter dirt bikes (for example the manufacturers make lighter weight pistons specifically designed to be lighter weight for racing but those pistons are made for one race or a few hours of driving on and then you throw them out) so they can race around the track faster, but not everyone who drives a dirt bike wants to have a lighter dirt bike because not everyone who drives a dirt bike races it. I specifically want thicker compression rings on a newer bike as I don't care if I lose a few high end rpms as I don't race. What I am saying is I would like to see a 2 stroke dirt bike built with tolerances farther away from the minimum in certain places but still using technology to make it more fuel efficient and better performing.

I am thinking about doing a snowbike conversion on my 400f. Has anyone done this and if so what all needs to be done besides heating the carb with extra coolant lines around it. Tia

So I have a unique issue that needs input from other fabricators. So I'm designing this cell phone holder to mount on top of my cyclops rally light putting it in more of my line of site just above my trail tech head unit. Now I've come across this problem where I need low profile usb passthrough bulkhead type fitting that doesn't exceed .6 inches. It's a machined piece of aluminum that will be milled out to hold and charge my phone covered with a lexan sealed lid. Now the fittings I'm finding are typically running .818 in size meaning I would need to increase my thickness of material which I'm desperately trying to avoid.

Hey guys, I really appreciate you taking the time to read this and possibly give me some help. I have a 1979 Honda XL185s that I have rebuilt and am to the point of wiring it up. I picked up the bike for $50 and it came with no wiring. I wanted to do custom anyways. I am converting to 12v with an antigravity 4cell 12v battery, 12v regulator, along with new oem style CDI, new coil, new pulse generator, ITS ALL NEW and fresh. I am not running any lights, all I need is to wire up the ignition and charging system, kickstart only. Problem is my new reg/rec has different colors than oem with no instructions, the coil I have has an extra wire compared to oem, I’m running a simple two wire on/off keyed ignition switch, subtle differences that leave me confused on where to go. Long story shortish, here is a list of what I have with color of each wire Any help you could give as to where to go with what is much appreciated, I know a few are probably obvious and simple but I’ll list them anyways for full coverage. Ignition switch (in-line fuse coming off of red wire, going straight to pos on batt) Black Red Reg/rec 2 yellow Red Black CDI Blk with female blade connector Two green Red/blk Blue/white Blk/white Pulse generator Blue Green Coil Blk/yellow Green Alternator Yellow/white Yellow Pink Red/black

Hey everyone, I’m new to my drz 400 and have now spent a couple hundred dollars getting it to where I want it to be. Now I’m at the point where the only thing I need is a exhaust with a good flow, and was wondering if it would be possible to fabricate my own header and pipe , and simply attach the stock muffler on the end ? Thanks!

Here's some pics of the double decker bike storage rack I made for my two 'kid' bikes. (TTR90 and BW80) (and yes, they really are for my kids) I wanted/needed to free up some space in garage, and be able to freely move them around as needed. Plus, the upper one is at a good height for service. Designed on Google Sketchup, fab'd and MIG welded at home. All 2" square tubing, except the sliding sleeve, which is 2.25" square. The lower legs and 'spine' are 3/16 wall thickness. The 'upper' level is 0.090" and 0.110" Plywood is 3/4". Caster wheels are 1/2-13 threaded direct into the lower legs. Pully system is 1Ton, worm gear hand crank boat trailer winch from HF. Approx 26" x 52" foot print, 6foot total height. Probably weighs 60lbs. I use my cordless drill to raise and lower the platform. Can use hand crank as backup. I load tested it with my fat butt, and Im 6'6" 230lbs. Enjoy the pics.