Need some advice please

[tweathers]

I started up my Blaster the other day since it is getting close to riding season and heard a horrible knocking in the top end and considering it hasn't been rebuilt in several years I decided I may as well rebuild it before the season starts and I end up blowing it up. That is besides the point...I have a couple questions that I'm hoping someone could help me out with.

The person that I brought it to recommended a ProX piston since I am not building it up to race it is just my first bike and I want to keep it reliable. He called me today and said that it would be about a week for the standard piston to put in it but he could bore it .040 over and have it ready in a couple days. With the .040 over can I still run 91 octane mixed at 40:1 (I believe thats what it is...1 bottle of castor 927 to 5 gallons of gas)

Will there be anything else I should be aware of jumping the bore that much in one rebuild? I saw the break in procedures that LBWD wrote in here and I will be following that strictly so I can keep the reliablity of it.

Is there anything else I should do during the process or rebuilding the top end. there is no play in the connecting rod on the crank so I feel confident that the bottom end is safe for now. A friend recommended pouring some lucas in the bottom end then draining everything to be sure i clean it out real good in case I did drop anything down in there.

Also the guy doing the machine work on the cylinder said I should be able to re use the copper gasket that seals the cooling fins to the rest of the head. Is that a bad idea or will that be okay?

Also not related to the top end but I can't seem to get it into 6th gear. It just will not go in I can get the revs high enough but if I try to shift it just feels like there is no gear to shift into. Any suggestions on that?

Thanks in advance for any advice you can give.
Tyler

 

[4cfed]

well. i ran vertex piston in my 2001.. had well over 100 hours on it.. and still had 140+ compression!!

yes its fine to bore over that far, you prob dont need to but it wont hurt anything, and yes you can still run 91.. you dont need to up the octaine tell you up the timing or compression... boring it over isnt giving you more power ( maybe half a hp)

wiesco and vertex are the only pistons i would use personnaly!!!

as for the gears... its 1 down 5 up ... you should already know that lol.. ( could be like my wifes 200e honda nutral is all the way up than 5 down!!.. or a yamaha 200 nutral al the way down than 5 up lol

 

[mr_3_0_5]

are you sure your counting the gears right. its one down five up.
only bore as much as need to get the scrapes out..
mix gas 32 to 1
id recomend a wisco piston.
get a new gasket for the top end. they are not that much on ebay.

 

[mr_3_0_5]

haha you beat me fed.. lol

 

[4cfed]

4cfed FTW!! lol

 

[super noober]

im quite surprised a machine shop would tell you to reuse the copper head gasket.. its a "crush" gasket and has a little lip that crushes down the first time you use it so its a one time deal. probally wont hurt anything and might be ok but sh*t, for the money you should just get a new one.

 

[rideyamaha09]

I'd recommend getting a wiseco piston, and only boring over one size unless more is needed. That way you can get more rebuilds out of the topend. I also have heard that the copper gasket can be reused but i would just get a new one, only a few bucks and then you don't have to worry about it. Probably wouldn't be a bad idea to replace the wrist pin bearing while you're rebuilding, its only about 10-15 bucks.

 

[doc_speeder]

As long as it's a quality forged piston, you'll be OK. As others have said, the gasket is too cheap to consider reusing.
Only bore as much as you need to. There's no advantage to boring more than necessary, and you'll shorten the useable life of your cylinder.
Not sure on the 6th gear thing. Pull it apart and check it out.

 

[tweathers]

Thank you everyone for the help. I will be getting a new gasket and rideyamaha09 I am replacing the bearing too. I'm just not replacing the bearing in the bottom end for obvious reasons since I'm not splitting the case. Also the only reason I am going .040 over instead of the minimum is because no one locally seemed to have the pro x piston that I needed locally so I am not the only one going through this process this time of year. Also I plan on getting (i know this may be a forbidden thing to say on the blaster forum) but I am planning on getting a Raptor 700R as soon as I can afford it and keeping the blaster for the nice easy rides. After all I am 235 lbs still riding a Blaster. I either need to do some serious mods and make it unreliable or just get something bigger and being so close to the dunes I figure a 700 Raptor will take me anywhere I need to go through the dunes. Well thanks again for all the help!!!

One more thing to add...I found a website a long time ago that was a great site for parts. Can anyone recommend a good website for parts?

 

[yb200]

just buy a wiseco piston from ATV Parts, ATV Tires, Dirt Bike Parts & Motocross Gear | Rocky Mountain ATV/MC for the size you need.....dont bore more then you need to just because they cant find the right piston