1983 ATC 250r Restoration

[brandonlowe2]

Yea I see exactly what you are talking about..... I will check when I get home. Good grief I hope thats not what it is or this just turned into a nightmare

[rgthree]

It the intake is 60mm C-C on the bolts then this...
http://r.ebay.com/30XTht It will fit a 38 with a bit of stretching

[Rob Canadian]

Yea I see exactly what you are talking about..... I will check when I get home. Good grief I hope thats not what it is or this just turned into a nightmare

Most part just a gasket I would think. Thanks to the keen eyes of the members you can order up the correct stuff for the 300R kit.

[OZQUAD44]

Doesn't look like nightmare at this point. A Head gasket, new carb, and new carb boot aren't the end of the world, and at 700 it is still reasonably priced, but I would carefully go over the machine. Since it looks like you may be up for a head gasket, I would Pop the head off and visually Check the barrel and piston before kicking this thing into life.


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[brandonlowe2]

Thanks a bunch guys.... I really appreciate it! I think I am going to send the engine up to yaegerb and let him do it right for me

[Onetrackmind]

Thanks a bunch guys.... I really appreciate it! I think I am going to send the engine up to yaegerb and let him do it right for me

I think that is a fantastic idea...he will definitely take care of you


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[bad to the bone]

Update on this?

[brandonlowe2]

Waiting on parts to come in.... got everything in but the carb. It "should" be here sometime this week

[brandonlowe2]

well... yaegerb has been helping me and teaching me lots of goodies about what to look for and all.... last night I finally got the cylinder head pulled off.... and ohhhhh boy check this crap out.... Got it pulled off... cleaned up.... the new gasket fits fine, but, check out what was under the gasket.... the weirdest looking tool mark (or something) i've ever seen....

[atc300r]

You should lap that head and cylinder gasket surface before you put it back together.Those punch marks are ugly..

[barnett468]

maybe I should just got for a 34mm carb?

Depends what your goal is and whether that cylinder has also been ported, but unless you like to ride at full throttle and max rpm all the time, a 34 will be a MUCH better carb . Also, you do NOT need an uber fancy Earthscorcher Octojet carb with a parabolic slide made from prefabulated amulite etc . A simple, authentic, (not chinese) 34 mm Mikuni round slide VM 34 will work just fine.


PREVIOUS KAWASAKI INTERNATIONAL R & D PROJECT ENGINEER AND ATV DEPARTMENT SUPERVISOR

[barnett468]

well... yaegerb has been helping me and teaching me lots of goodies about what to look for and all.... last night I finally got the cylinder head pulled off.... and ohhhhh boy check this crap out.... Got it pulled off... cleaned up.... the new gasket fits fine, but, check out what was under the gasket.... the weirdest looking tool mark (or something) i've ever seen....

Well it looks to me as though atc300r has also been teaching you a lot of things also.

I Googled all the following info because I have no experience doing any of this and read that those punch marks on the cylinder were added by someone by hand . It said that some people do that to help keep soft gaskets like cork and paper in place that have no bolts thru them but it has no benefit in your app, and if the edges of the "divots" have not been sanded flush with the cylinder, they can prevent the gasket from sealing properly which s why atc300r suggested surfacing the cylinder . The head may also be warped which is why atc300r suggested surfacing that too.

It also said that one can take a razor blade and place it at a 45 degree angle on the cylinder then push it across the "divots" as if you were trying to scrape a gasket off and see if it gets caught on them . If the blade does not catch, they may have already been smoothed/sanded flush . If it does catch, they should definitely be smoothed . I copied and pasted one method I read on how to do this if the damage is not excessive.

"HEAD AND CYLINDER SURFACING

1. Place a long closed end wrench over a stud.

2. Place 2 nuts on the stud so the stud protrudes around 1/4" above the top nut . Grade 8 nuts are the best to use because the threads on grade 5 nuts may stretch, especially if they are made in china.

3. Tighten the nuts together firmly using the wrench you placed on the stud for the bottom nut and another closed end wrench on the top nut.

4. Hold the cylinder firmly and turn the bottom wrench counter clockwise . You can reinstall the cylinder on the engine to hold it if necessary . If both nuts turn, they are not locked together tight enough and this can damage the stud threads.

5. Once all the studs are removed, get a couple full size pieces of 120 grit wet/dry sandpaper, a felt pen and some water or WD40 or similar product light oil product then find a nice polished granite countertop or polished marble floor tile . If you don't live in a million dollar house that has either of these, you can buy a piece from home depot etc or you can use a window pane but it's pretty friggen hard to surface a cylinder on a window pane . It's easy to do the head on one.

6. Once you have located a flat surface, clean the head and cylinder off with cleaner then place the sandpaper on the surface you are using . It sometimes helps to tape it down in the corners . Then color the gasket sealing surfaces with the felt pen.

7. Put some water or WD40 on the sandpaper.

8. Place the cylinder on the paper and put light downward force on it then rotate it several times then gently wipe the surface off so as not not wipe any remaining felt pen mark off and inspect it . Once ALL the felt pen mark is removed, it is flat . Once you think it is flat, repeat the process once more to double check . Do the same with the cylinder head, however, you need to put moderate downward force on it to get the paper to cut into it . You can also push the head back and forth on the paper as long as you keep it fat . The cylinder is harder to do this with.

9. Once both are flat and clean, reinstall the studs by applying light oil or grease and turning the top nut until the studs are fairly tight in the cylinder . If you have a torque wrench, you can use that and tighten them to around 16-18 foot lbs or use 2 lbs less than the factory spec if they list one.


CYLINDER AND PISTON MEASURING

You should get the cylinder measured front to rear and side to side around 3/8" from the top, in the middle, and 3/8" up from the bottom to check for taper and concentricity . Measure the piston for wear."



PREVIOUS KAWASAKI INTERNATIONAL R & D PROJECT ENGINEER AND ATV DEPARTMENT SUPERVISOR

[brandonlowe2]

(yes, I realize this is exactly the same way I started my Tri-Z rebuild post I just made)

Well well.... after 6 months.... I have realize one thing. These rebuilds don't happen over night! I have been working very hard (not NEAR as hard as the guys helping me, whom you will find out about in posts to come) on getting this '83 pieced back together... and in the meantime I moved, sold a house, bought a new house, renovated it, and moved into it. SO, its been a crazy 6 months. But, I can finally see the light at the end of the tunnel on this build.

I will have more pictures, and quite a story on this one, coming soon... but, for now I leave you with this....

[brandonlowe2]

and.... maybe this teaser.....

[brandonlowe2]

Here is the rebuilt shock.... before and after.




AND.... (drum roll).....