davefrombc

I made it 388 Dan

Here is a link to a site with the service manual for the 2005 Sportsman 500. It won't let me download the manual unless I sign up with the site so I'm just posting the link for you to do as you wish.. You can view the entire manual online , just can't download it . https://www.scribd.com/doc/51630928/2005-Polaris-Sportsman-400-500-Service-Manual-NoPW

It's good to know your limitations and those of your machine , but it's fun ( and occasionally painful) to exceed them. I must admit at 75 I tend to nudge them more rather than push them.

Look for a blown fuse somewhere in the main circuit from the battery. That may be all the problem with the ECM and the rest of the circuits. If there wasn't a fuse or fusible link the whole wiring system should have gone up in smoke within seconds. As far as the ECM and other sensitive electronics goes with reversed polarity, they should have blown within milliseconds of the reversal.. Too fast for you to see anything happening. Since you say it was hooked up for minutes without visible smoke or damage I'd look for a fuse or fusible link and hope it saved the day .

Since I am into trail riding, hunting and pulling tasks around home I much prefer the low end grunt of the 4 strokes. Add to that the convenience of not having to mix the fuel and it's 4 stroke without question . Racing is a different matter. 2 strokes shine there, but unless you're race crazy, go with 4 stroke. They're so much more convenient and versatile .

There have been some members found that without the breather box and air filter their machine does go lean and bog as you say yours does.. You could try restricting the air a bit either with the choke or just by partially blocking the intake with your hand and see it it will rev up ok .

I think only you can decide if it is worth it or not .. Can you do the repairs yourself? What will the parts cost? how does the quad run? Motor ,transmission and tires good? Other quads around for comparable price that may be in better condition/ need less work on them? I never let the year bother in my decisions if the motor and transmission are fine . My own Quad is a 1991.

My own quad is a 1991 Honda Fourtrax 300FW, bought used 6 years ago. Only major repair I've done on it is replaced the rear axle and wheel hubs 2 years ago due to the splines on the axle ends and the wheel hubs wearing out ( a common problem on many of the older solid rear axle machines). I replaced the battery a couple of years ago and replaced the brushes in the starter this year. That's it for repairs. A friend bought a 1988 2 wheel drive Honda Fourtax 250 that had really been rode hard. The rear axle swing arm and torque tube was all cracked up.. Some welding and gusseting with my wirefeed and the machine has been good to go since. In my opinion, you can't beat a Honda for reliability and longevity.

In BC, other than the cheapie smaller Mainland Chinese offerings , the Polaris is likely the least popular. I don't know about newer models , but the older ones gained the nickname "Pullhairis". It would be hard to go wrong with any Honda , Yamaha, Kawasaki or Suzuki if it was kept reasonably well maintained. One machine that far too many dismiss as " Chinese junk" but actually is one of the best is the Kymco... built in Taiwan.. Kawasaki , Yamaha and most likely Honda still have ties with Kymco. Kymco originally built parts for Honda before branching out on its own. It now is one of the largest manufacturers world wide for scooters, and supplies motors and other parts for some of the big name Japanese quads .. BMW ( yes , that BMW) has close dealings with Kymco. I am not familiar with any of the larger mainland Chinese made ATVs, but I've seen some that look very good. Don't kid yourself . The Chinese can make some cheap junk, but they can also make some products that can compete on the same level as the best of the world.

Why not the nice shiny rims? . They look good .

Excellent job. I think there's going to be one very happy young lady.

Is it possible the brake is dragging? Often a vehicle ( quad or car) will have less brake resistance in reverse and be able to move quite easy, but lock up in forward gears.. Can you roll the machine fairly easily when it is shut down and in neutral? If not , check for a frozen brake .

I can't help on the replacement bolt, but if you take the threaded part of the broken one to a place selling metric bolts you can match it up there. According to a chart I found a bolt with a 10 mm head is normally 6 mm diameter, and has a 1 mm thread pitch.

You can get slick guides used to center pilot holes for installing door hinges. Replace the right twist drill bit in the appropriate sized one with a left twist drill bit and use it to drill the broken bolt. The bit guide will center the drill bit and prevent you going off to the side and messing up the hole and bolt, and the left twist drill may extract the bolt as you drill. If it doesn't, you will have a centered hole in it to use a regular extractor on. Here is a link to the set I'm talking about offered on Amazon. The set would be handy for a lot of projects that require a well centered drilled hole . https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=Migiwata+7Pcs+HSS+Adjustable+Self-centering+Door+and+Cabinet+Hinge+Hole+Opening+Drill+Bit+Set+

It may be getting too much air, running too lean to start .. Try replacing the air filter and other stock inlet air components and see it if starts and runs much better. Some quads need the air filter installed to run properly. Several members have run into that problem before.

You should be able to have that welded up and reinforced without too much problem. You just have to be sure to keep it all in alignment while doing it

The problem likely lies in the voltage regulator. I would try to borrow a known good, compatible one and try it on your machine first . If that does not fix it , it may be the stator.. Before tearing into the machine to try changing it out, I would download the service manual and follow the tests outlined in it .

with the engine running you should have between 13.5 and 14.5 volts DC at the battery terminals. If the lights are on or other accessories are in use the voltage will be a little lower but it shouldn't drop below about 12.5v . The alternator puts out about 25v 3 phase ac that the voltage regulator rectifies and limits to a max of 14.5v DC

There should be a "hook" on the spring that clips over the lower lever in your pix, and the other end of the spring likely just sits against the case. The longer part with the hook hooks over the lower lever arm next to the bent down tab of the upper lever. Here is a drawing of the assembly :

The edges of the U cup seal(s) go towards the outlet. The pressure in the system when you press the brake forces the lips of the cup out to hold the pressure. If it is backward the pressure pushes them in and bypasses the piston. That easily could be the problem . You wouldn't be the first to accidentally put them in backwards 😇

No, there should be no blow back into the reservoir when you put pressure on the pump , only on release should any air blow back, and only until the air is out of the pump. it sounds like the plunger on the master cylinder has a defective seal. There is no check valve on the master cylinder so when you release the brakes the wheel cylinders push the fluid on the lines back to the reservoir. If there was a check valve , once the brakes were applied they could not release. I think you got a defective master cylinder. There are videos on rebuilding them on Youtube and rebuild kits are not expensive.

You should.. I don't know if you're familiar with bleeding brakes , so I'll toss this in . When you pump, while the handle is down in the pumped position, close the brake bleeder vqalve so the master cylinder has to draw from the reservoir rather than drawing back from the line . Same goes when just at the master cylinder itself .. block the outlet with your thumb when releasing the brake handle . You should get pressurized fluid on each pump after the first .

There is very little volume per stroke on the master cylinder , so I would suggest just keep bleeding the system until all the air bubbles out. A faster way , but a lot more expensive is to buy a tool to do a reverse brake bleed. It's a handy tool if you need to vacuum test switches and air motors as well as bleed brakes on any of your vehicles. Here is one on Amazon.com: https://www.amazon.ca/Performance-Tool-W87030-Automotive-Bleeder/dp/B013VUZ7WG?th=1&psc=1&source=googleshopping&locale=en-CA&tag=googcana-20&ref=pd_sl_54ilvkye00_e

There's one in page 2 of the sites service manual list in the downloads section. You'll need 10 posts before you can download it . Here's a link and info you need to read before trying to download it. Basically , you need 10 posts without spamming the site to get them . This manual covers the 250 to the 400.

That o ring missing might be your problem. That might be the source of excess air entering the system.. Is the slide of the main jet all the way down at closed throttle ? if for some reason the throttle cable is holding it slightly open that could also be your problem.