How much would 250r motor work cost?

[Honda Lover]

I was looking at an 84 250r, that supposedly needs motor work, because it lost compression the last time it was run. So, i figured it would need to be bored out and then get a new piston, or is it probably something else? , you tell me. So, can anyone give me an estimate of how much this would cost. I have a friend who could help me with the dissassembly and reassembly, but i guess boreing it out would have to be professionally done. Also, would any of you buy an atv in this kind of condition, yourself. I'm just wondering because if i ever found one cheap that had a problem like this, would it be worth taking a chance and trying to fix the motor problems?

Thanks,

[max]

I Spent About 150 On Parts And Bore Job For My 84. As Far As Labor. I Did It My Self. Dealer Will Probably Hit You At 4hrs At Whatever Their Hourly Rate Is. Guessing!!. My Advise Would Be To Get A Manual And Do It Yourself. Save Money. Learn A Little. Good Luck
Max

[oddball3]

All the trikes I bought were all fixer uppers, My 250r needed a complete rebuild, Rod,crank bearings and seals, cylinder bore piston and rings.
My wifes 200x needed a shifter shaft.
The 70 I just got needs a topend rebuild.
So yes I would buy a trike if it needed fixing or rebuilding.

[TeamGeek6]

I have 400 - 500 in parts in a total engine and transmission rebuild - every bearing and seal and gasket in it - the entire engine back to "new." I did all the work including cylinder work, (except crankshaft press work) but it didn't need bored.

If you plan to keep it, plan to do it all while the parts are still available. Bearings will be around for a long time, but plastic and rubber parts, especially chassis parts, will become hard to find.

Main thing on the cylinder is to get a T-bar and micrometer and measure the bore in 8 places and determine whether it needs boring, or just honing.

The most important and expensive part is the crankshaft work, that takes a press and jig work. Any GOOD machine shop (not Uncle Goobers back alley shop!!) can do it.

It isnt hard to take it apart and put parts in, but its an art to assemble it correctly and make it run properly - especially a 2 stroke engine. One wrong move on a bore and hone job and its toast. Little bit of grit in the trans and its toast.

[OldSchoolin86]

Main thing on the cylinder is to get a T-bar and micrometer and measure the bore in 8 places and determine whether it needs boring, or just honing.

Just a tip to save you some unnecessary measuring:

Most of your wear will be in the direction from the front of the cylinder to the back. Measure a couple times up and down that area and you'll know for sure.

Also most of the bearing will be around a long time but honda likes to slip in one from time to time that only they offer. Case in point in your liquid R there is one in the trans that has a special cut in one of the races you can't get at bearing houses. You could get one like it and have it machined to match though if you had to.

[sandpuppi101]

Old schooling is exactly rite,most of your cylinder wear comes frt -back ,a egg like wear will happen! Take off the jug take it to your dealer and have them dial bore gauge it ,I am guessing wore rings,To bore is not always cool if you don,t have too,Unless you have major gouges or something!!!

[hoser]

Just a tip to save you some unnecessary measuring:

Most of your wear will be in the direction from the front of the cylinder to the back. Measure a couple times up and down that area and you'll know for sure.

Also most of the bearing will be around a long time but honda likes to slip in one from time to time that only they offer. Case in point in your liquid R there is one in the trans that has a special cut in one of the races you can't get at bearing houses. You could get one like it and have it machined to match though if you had to.

Their is no such thing as unnecessary measuring on a 2 stroke, I have seen huge differences above and below port openings, I guess it depends alot on how worn the cylinder is, how much it was abused, some like to wear out 2-3 pistons and rings between bores, it also depends how thin the bore is from over bores and how many times someone over heated the engine during its life, you really see all this damage when you use a fixed hone stone hone and give it a lite hone, amazing how much of the bore the stones never touch on a real worn bore.

Bottom line is follow the instructions in the factory service manual for inspecting.

The below was taken from my CSI section of my web page its the internal discoveries of my TRX engine.
===========================================
I put a lite hone on the cylinder to see just how straight it was using a ridged Sunnen AN-112 hone not sure how you could do this with a flex hone.


I know its sometimes hard to see in pictures you loose so much in a pic, so I put some small red and blue arrows pointing at some of the hi and low spots, the blue is high spots and the red is low spots I didn't mark all of them just a few to give you a some sort of idea.













A ball hone wont show this.

[hoser]

I was looking at an 84 250r, that supposedly needs motor work, because it lost compression the last time it was run. So, i figured it would need to be bored out and then get a new piston, or is it probably something else? , you tell me. So, can anyone give me an estimate of how much this would cost. I have a friend who could help me with the dissassembly and reassembly, but i guess boreing it out would have to be professionally done. Also, would any of you buy an atv in this kind of condition, yourself. I'm just wondering because if i ever found one cheap that had a problem like this, would it be worth taking a chance and trying to fix the motor problems?

Thanks,

How much is he asking for the bike?

No compression could be cheap as stuck rings from a mild seizure, replace the piston and rings, hone and go, it might be as expensive as the cylinder is on the last bore and you need to replace it.

Since it dont run the owner should allow you to remove the top end for inspection so you know the cost to get it running again, but its always nice to CSI a engine to find out exactly what caused its death, if you dont chances are it will happen again soon.

Their are many things that can cause it to lose compression, stuck rings from lack of cooling, oil caused by lean jetting or a air leak, hole in the piston caused from detonation.

Here are so engines that have failed and their CSI's
http://12.227.214.171/CSI.htm

Jetting page
http://12.227.214.171/jetting1.htm

Detonation page
http://12.227.214.171/Fuel-Squish-Detonation.htm

You will need to join my message board to read some of the material, sorry.