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My CR85 -- Yeah!

51K views 90 replies 16 participants last post by  aarontillison 
#1 ·
Well how shall I start this? Umm I knew I wanted a 2-stroke mini to ride around with my brother on his SSR140 and thanks to some friends on here I ended up with a 2003 CR85 I picked up for a cool $400 :D

She was in bad shape to say the least, but I was excited to take on this project first time for me. As soon as I got the bike home, put it on the stand and began taking it apart. So soon that I did not take a before picture :( , but I digress. I wanted to strip the bike down to paint the frame either red or black, and put everything back tighthen all the bolts replace all fluids, basically bring her back to a respectable state. Thus it began..

Where I was when I first thought to take a picture(s)


Big parts off, ready to be cleaned or thrown away. I got rid of all the plastics, I'm thinking of going either black or white plastics.


In a mess there is only a thrown. This is where I thought, what did I get myself into. Lol


Cleanish parts.



Something about noise emission, oh government! :arsenal


I went red!


New goodies! Purchased, new bearing, seals, bars/grips, sprockets (stock 14? up front and 47 in the rear), new gold chain :D , new top end.


Got bored one night and decided to piece er' back together. Worked from about midnight to 5:30am. :D I later realized the shock was backwards. Doh! The two mistakes I made was the shock and I put the subframe on before installing the airbox. Everything else was not too bad.


And as she stands now.


Clearly I am not done, infact I've only started. Next up is the conversion ! I want to get plastics before looking into all the SM goodies, although my family/friends like the naked look. o_O and I'm looking for some used SM wheels 12" or 17" I'm indifferent so long as the price is right.

Now I haven't got her running right, I'm hoping its something rather small and not a tear down all over again. It takes several kicks to get going and I have to give her some gas but then she will idle well and the motor itself sounds good no odd noises. Put her in 1st -- stall. Unless I really get the RPMs going and feather out the clutch it will stall. Once she gets going she runs like a champ! Riding a 2t is like learning to ride ALL over again, seriously! And she spits oil out where the exhaust connects to the motor, but I think this is the gasket or spring as I reused the ones that were there. All in all I'm diggin it! Thanks for all the help dudes!

Diego
 
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#3 ·
Yeah I'll probably go that route, I can't even find white plastics. Lol Plus with the black tank and all.

I'll have to check my plug and get back.
 
#6 ·
32:1 ,eyeball though. Its weird because once I can get it rolling it runs well, it even idles well. Just when I put it into first and try to get it going it'll stall.

Yeah Toadmeister, this was my only fear with a two-stroke. But when I get time I'll get to work. I have the Service Manual as a baseline. It was like this when I picked her up, but I figured the carb was all dirty from sitting.
 
#7 ·
Is it clutch drag? You shouldn't get much drag from the clutch. What oil is in it? And try taking almost all the slack out of your clutch cable and see if more pull helps it disengage.

If it still drags, then you may have a scored clutch basket... where the plates eat grooves into the fingers which then hold the plates from separating.

You can often file them out and/or smooth the notches out (carefully, not all the way, just the absolute minimum amount to get the clutch to disengage) the first time or two... but eventually you'll be buying a clutch basket. If that's the problem that is.

I'd run MTL in the tranny... helps the clutch last longer, and it helps the basket live longer.

I just pulled all this out of the dark corners of my memory from about 15 years ago... when I was maintaining a CR250's and KX250's for MX. But a 2X is a 2X ;-)

 
#8 ·
sounds right to me NYC, you memory has served you well.

Nice bike. you have put alot of time and effort into it so far so dont undo all your good work. look at the plug and see what it going on. it does sound like it could be the clutch if its only doing it in 1st.
 
#9 ·
Yeah guys I've been slacking a little. I need to make myself a schedule with task on it to complete by certain dates.

As far as the clutch stuff, I don't know what oil it has in it. I was supposed to crank it up and let it warm up to change the oil. I was just going to use some 10w-40 MC oil leftover from the big bike. But I'll look into the Motul stuff. Do you need a specialty tool to remove the clutch basket? I saw some Boysen baskets for like $210 on MCSS, not bad right?

Grnman, I still havent pulled the plug to see what it looks like. :headshake
 
#50 · (Edited)
dont over complicate things with this bike.

carb- clean real well. soak the brass in anmonia, and make sure it stays clean.

jetting- here in FL use stock jetting. it works the best.

oil/fuel: 32:1 dont change it. dont tune your bike trying to run different mixtures. use the recommended mixture, and then jet the carb (but again stock settings are dead on). any motor builder i talked to says motul 800 2t. i run amsoil dominator in our CR and it flat out rips and is clean enough on the inside to eat off of.

trans oil: use rotella from walmart. 30w is good enough. dont buy expensive oil as you are tossing it out after a day of riding.


to change oil, you can warm it up on the stand while in gear, but honestly you will change it so much that it really does not matter.


people try to get crazy with these bikes and fail. keep it simple and it will be your best friend.

If you need a hand with it, let me know. i am local.
 
#10 ·
If it does end up needing a basket, go here:

http://www.peracing.com/products/clutbask.html

Can't beat the PE units. They run about $120.

You will need to grind out the rivets on the stock basket to get the gear off. The new basket will come with the screws to reassemble. Use red loctite on the screws.
 
#11 ·
Thanks Toadmeister. I'm going to change the oil in it today and adjust the clutch out my nyc said and go from there. Oh and pull the damn plug! :lol:
 
#13 ·
Alright, I'll do that. Just got home from work, got my book. Doesn't look like I need any special tools. I'll post pitchas when iz finish baws.
 
#14 ·
Alright bros, I can say I may have officially F things up. I cannot get the clutchcover off. These stubborn ass dowel pins (one of them anyways) is just holding and will not let go. So I got nowhere today, I'm just going to walk away from it and hope for better luck tomorrow.
 
#15 ·
dang. so you have the bolts out, the water pump and impellar out, and clearance to pull off the cover and it wont budge? I sometimes use a SOFT (rubber) mallet to tap on cases halves or 1 piece clutch covers (like on a cr85) to get them loose if they dont come apart easily.
 
#16 ·
Yeah, I got all the bolts off. But the water pump, and impellar are underneath the cover which I can't get off. I tried hitting it with the mallet like I did when trying to remove the cylinder but It just is not budging, its one of them. The other are up I can lift most of the cover off just the one on top is stuck. And I'm ruining the paint big time. Lol
 
#19 ·
Well fellas, I'm an idiot and do not know how to count. I missed a bolt, could have sworn I counted 10 bolts in my hand. Thanks toadmeister, after reading your message I said "Eff it, I'll take off the other bolts." which I thought were to hold the water pump. So I dont know exactly what I am looking at here, everything appeard to look good to me. The untrained eye.

Pictures:




Yeah, I royally F'd up some of the paint, and that gasket around the cover and maybe the cover itself. But no worries mates!


Check out pictures of the old piston I pulled out. Looking at the outside of this piston anyone think the cylinder walls could be scorched, leading to low compression? -- The idea was tossed around on a sportbike forum I visit.





Thank you guys again. :bowdown:
 
#20 ·
The amount of damage on the piston would tell me that the cylinder is scored. But, you won't know until you pull it apart and verify. Also, it looks like you damaged the case, lower right corner, above the paint damage on the frame. I have a hard time believing that the cover will seal properly against the case. At least get a flat file and smooth that area before you put it back together.
 
#22 ·
ive seen worst. i would just hone it unless the scores are really bad. it was still running just low compression hone and new piston will make it ten times better. basket looks killer. 400 bucks great score.
 
#24 ·
:| I'm not even a weekend warrior. I'm more of a neighborhood nusaince :D a bigbore kit did run through my mind but they cost around $400 to $600! One thing that sucks about getting a bike at such a cheap price is the fact that big purchases hurt more. Like buying a pair of $1K wheels! Thats 150% more than the entire bike, Lol.

Pscook, I know I royally F'd up the case. I'm going to file it and see if it will seal up. If it does (Fingers crossed) I'll post a video of what exactly is happening.
 
#25 ·
before you put your top end back together take a a close look at your cylinder walls. all you should see is cross hatching and a consistent coating. if you notice any vertical lines or places where the coating is gone you might as well just throw down the $375 for a big bore kit because you will be spending that much on a replated cylinder from millenium anyways.


and i know you were going to already, but replace that piston and ring.

for the case I would try to get away with using JB weld.
 
#26 ·
Scottie, where can I get a bigbore for that price? I saw lukesracing has a 102cc for $600 plus the shipping price of sending my old cylinder back. Im going to hope the case seals, if it does then ill get the bigbore.
 
#27 ·
First thing I would do regarding the case is to draw a file across the damage, bridged across the case. it will knock off the high spots and expose the low spots. You can repair the case edge with JB weld, it just takes a bit of imagination and patience. JB runs like water, so you could build a dam and simply float the JB and file it, or you could find some of that quick repair paste and form a bead and press it on. once you build it up just carefully draw the file across and knock it down, then carefully reseal the gasket surfaces. It's a bit tricky, but you can do it. or roll some repair paste over the damage and bolt the cover on it, using the paste as form-a-gasket. *******, but possible.

One last option, which may be the best- Scour for some cases on ebay and rebuild that sucker, or even swap in a known runner. You might have to drop another $400, but then you are set with a spare set of internals. Here's an option, might be an opportunity in the making.
 
#28 ·
Oye vey. I have to try! I ordered the gasket which should be here Monday and im going to try and seal it up if not just throw the money into a running engine. :/
 
#32 ·
Cool, I've heard some iffy stuff about the customer service at FM but the work is top notch. It seems I'll have to wait though,

Forward Motion will be closed for the month of September so please don't send packages from
August 15, 2011 until September 25, 2011. Packages sent between those dates will be recovered safely but no work will be performed.
 
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