Two Stroke Motocross

Two Stroke Motocross Forum => Technical => Topic started by: wikid on July 11, 2011, 03:58:56 AM

Title: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 11, 2011, 03:58:56 AM: Hello ladies and gents, I got into a 3rd gear tangled mess with what was a prime morning at the mx track with my buddy, but ended up as a de-railed chain cracking my left side case. I have a new left side case on the way but am a virgin to splitting the cases. This seemed as though it would be as easy as a two stroke top end but now I am seeing I need a fly wheeler puller and about 3 other specialty tools. Am I wrong? (Please say yes)

Also I am wondering what parts I need when going back together. Base gasket, primary drive seal? any more seals?

Any help is greatly appreciated!

(and does anyone have Moto814 Steve's email?)
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: MyckMcClung on July 11, 2011, 04:51:18 AM: get a full gasket kit, top and bottom, replace everything, you will be glad you did down the road. Also find a manual online, and study it, and print out the pages needed for the tear down, reassembly, and the specs and keep it handy while doing the job.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: eprovenzano on July 11, 2011, 05:46:55 AM: Yes you will need a flywheel puller. When I split my son's engine, I took the engine to a local shop and they pulled "the flywheel for free. The only other "tool" I used was a freezer and the grill... I froze the bearings so they would drop into the cases, and I used the grill to warm up the cases so the bearing be easier to install. A rubber mallet will be your best friend as some things will need a little persuasion to be properly seated. It�??s not too difficult to do, but as stated earlier get a manual, and read it, again, again, and again. It�??s important you understand the steps involved.

One piece of advice, as you pull gears, etc, use a zip tie to keep the gears together, and in the proper sequence and to insure a gear does not get put in backwards�?� (yes I did, and had to resplit the cases�?� I put 1st gear in backwards)
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 11, 2011, 02:15:53 PM: Daaang, someone made it sound alot easier (inexperienced, obviously) like it would just be a sidecover pull and replace. Alright I'm off to find a manual and watch some youtube vids about it....any know of an online manual? Do you recommend replacing the bearings that came in the left side cover(used)? Thanks for the help, off to the bottom end of uncharted territory I go!
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: ford832 on July 11, 2011, 03:54:28 PM: It's not that difficult,just take your time and if need be,take pics of it as you haul it apart.It make it much easier as you can reference them upon reassembly.It's always best to replace all bearings,seals and anything else that shows wear while you're in there.Better that than tear it apart again a few months down the road.Pay close attention to your crank while you're in there as well.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 11, 2011, 04:30:33 PM: Ford832, Mr T. saying no to fourstrokes...yeaaa!

Last three questions(you can only hope)

1.I got a flywheel puller, I also need ta get my hands on a case splitter tool?
2. Do those 4 bearings (primary drive,etc.) in the left case come in a kit perhaps? (Yea I dont wanna tear down this gutless wonder this far again so I'm going all bearings and seals)
3.I haven't ordered parts over the web in a coons age, whats the best/easiest site. I'm talking good chain/sprock deals too

4. Hang Loose!
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: SachsGS on July 11, 2011, 07:01:12 PM: How bad is the damage? I've welded many damaged cases (still assembled) without any problems. ;D
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: luthier269 on July 11, 2011, 09:50:01 PM: Also go to You Tube and watch some vids on how to split the case. Rocky/mnt mc has you tube vids on how to split the cases and assemble and do bearings.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: Coop on July 12, 2011, 05:57:25 AM: Indigo Racer Powersports is a sponsor here and offers a discount to forum members:

http://www.indigoracer.com/default.asp (http://www.indigoracer.com/default.asp)

I use them and RockyMountainAtv mostly. If I need an OEM part I have been using Ron Ayers because they are cheaper (shipping too) than BikeBandit. I am pretty sure Mike at indigo can get you OEM parts though.

As far as tools, you need a fly wheel puller to get the flywheel off. I use an air impact for the clutch nut so I never bought a holder. Do NOT use a screw driver to split the cases. Do you a search on google and you will see how folks have use pullers to split cases. Honestly I get ALL the bolts out (they are easy to overlook), place the engine on my bench, then use a soft piece of wood and a mallet and use that separate the cases. Just put the wood against the case half and tap it. I keep working around the case and once it starts to come apart it goes easily. Having said that, I have been rebuilding a lot of bikes the last year or two (I supply my nephews with bikes) so I may invest in a splitter for the next one as it would be faster and safer.

When it comes time to reassemble, follow eprovenzano's advice. Freeze the bearings, heat the case. Then heat the case with bearings installed and freeze the crank. Reassembly will be a breeze.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: eprovenzano on July 12, 2011, 07:18:48 AM: Coop has given great advice. I too didn't use a case splitter, just a rudder mallet. An impact wrench makes the process of disassemble so much easier. Since you have a flywheel puller, I think the only other tools needed are an impact wrench, and a rubber mallet. Two tools we all need in our tool collection.

Take a lot of pictures as you disassemble, it does really help. Search YouTube for vids, I'm sure you'll find something. A manual is a must!!!! It�??s a great reference. As I took things apart, I kept gears, bearing etc together via a zip tie. It made reassemble a lot easier. Honestly splitting the cases is not that difficult, it can be a little time consuming, but anything doing is worth doing correctly. While you have her apart, clean the internals. I used soap and water; yes I borrowed the wife's dish detergent and scrubbed everything. I then sprayed all parts down with WD40 prior to reassembly.

Just take your time, as you'll really be proud that you were able rebuild it. Start a rebuild thread so we can follow your progress.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: SachsGS on July 12, 2011, 07:59:44 AM: To replace a damaged left side case you need only to pull the top end,flywheel,countershaft sprocket and side case fasteners.The clutch side of the motor can remain assembled-no need to touch it.Be careful as Hondas use a lot of shims in their transmissions.

In theory centre cases are matched sets and should be replaced in pairs. ;D
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: Coop on July 12, 2011, 08:49:43 AM: Normally I agree with your tech advice Sachs, but in this case I don't. I recommend completely disassembling and replacing both crank bearings/seals. No sense in putting it back together with used/worn parts. This way you shouldn't have to crack the cases again anytime soon (hopefully).
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: dogger315 on July 12, 2011, 11:21:59 AM: Quote
I am seeing I need a fly wheeler puller and about 3 other specialty tools.
Lots of info here, both good and bad.

The new case you ordered from Honda will come with all the bearings pre-installed. You will
need to purchase seals and retainers and, as somebody already pointed out, a complete gasket
kit (more cost effective than purchasing individual gaskets).

Since this is a ten year old tiddler, I recommend you replace all the circlips, shift pawls, shift pawl
springs, gearshift spindle spring, gearshift ratchet spring, right side crank bearing and all the seals
on the right side case. This will essentially yield a like new feel (shifting action especially), for the
bottom end.

Before you start, I highly recommend getting a Honda Service manual. There is a lot of useful
info, including seal depths, that isn't found in other manuals.

For tools, you'll need a flywheel puller and case splitter. There are many other ways to accomplish
these two task, but I don't recommend them on your first attempt. A good but inexpensive line
of tools is the Tusk brand sold by Rocky Mountain. They also sell a crankshaft puller/installer
that is very useful for this job.

I recently posted an engine tear down and rebuild pictorial using a CR500 engine on anther forum.
The basics are the same and the pictures and techniques might be helpful. Here is a link if you are
interested: http://www.allthingsmoto.com/forums/f-235/cr500-engine-build-pictorial-part-1-a-50432/ (http://www.allthingsmoto.com/forums/f-235/cr500-engine-build-pictorial-part-1-a-50432/)

Good luck with it.

dogger
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: citabjockey on July 12, 2011, 04:24:44 PM: Summary of a case split.
(http://s610.photobucket.com/albums/tt188/citabjockey/?action=view&current=TheGreatYellowBeast.mp4)
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: SachsGS on July 12, 2011, 07:16:06 PM: Hey Coop I was just trying to clarify the fact that a total engine teardown was not necessary to replace the damaged side case.While it is better to "bite the bullet" and recondition the entire motor the repair can be done in a simpler manner. ;D
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: ford832 on July 13, 2011, 02:01:47 PM: Quote from: wikid on July 11, 2011, 04:30:33 PM
Ford832, Mr T. saying no to fourstrokes...yeaaa!

Last three questions(you can only hope)

1.I got a flywheel puller, I also need ta get my hands on a case splitter tool?
2. Do those 4 bearings (primary drive,etc.) in the left case come in a kit perhaps? (Yea I dont wanna tear down this gutless wonder this far again so I'm going all bearings and seals)
3.I haven't ordered parts over the web in a coons age, whats the best/easiest site. I'm talking good chain/sprock deals too

4. Hang Loose!

Nothing else I can add to the good advice above wikid other than I prefer to use the proper tools whenever possible.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 24, 2011, 05:55:31 PM: Hey ya'll! Long time no update, but here I am with the scoot back together after a "good" Sunday afternoon of doing bike work. So here it is...big moment, fresh filter, oil, gas, chain/sprockets. One little thing going on in my mind all the way to putting on the last seat bolt......THAT GOSH DARN LAST WASHER! Yea, I figured it looked like too much of a "inside motor" washer and after the first kick over of the motor: Yea something doesnt sound right...sounded like a "loose" piston or something wasn't right, second kick....same sound, definitely not something right. Third kick and it's "locked"...stuck. Lord, I know I didnt attend church today and did bike work instead, but please just let it be something on the top end. Nah, it's gotta be that washer. So...without a manual and not seeing where it may have "fell" from, does anyone know where this "medium" size washer may be from? It can't go up against the four bearings. Does it have something to do, or bump up against the tranny? Quite a fun, new sort of realm of the two stroke world that I haven't wrenched into yet, and Im thinking I'll have to journey into there again! My buddy said "hopefully it's just something stupid in the top end" but I think it was us being stupid and playing the "wait to see if you have any parts left" game.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 24, 2011, 05:56:44 PM: I just remembered this: The clutch pull seemed alot harder than normal too after we got it back together.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: TMKIWI on July 24, 2011, 09:56:56 PM: Pull your right hand case cover off.
Its either a clutch thrust washer or something from the gearbox.
Not knowing what classifies as a "medium size washer" the right side is where I would start.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: TotalNZ on July 25, 2011, 01:20:12 AM: Hmmm i seem to remember a medium sized washer that dislodged easily out of the powervalve actuator.
Sounds like somewhere in the clutch would be a good start though.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: Coop on July 25, 2011, 04:40:11 AM: Quote from: TMKIWI on July 24, 2011, 09:56:56 PM
Pull your right hand case cover off.
Its either a clutch thrust washer or something from the gearbox.
Not knowing what classifies as a "medium size washer" the right side is where I would start.

Agreed.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: eprovenzano on July 25, 2011, 06:29:54 AM: You should have a repair manual.... :o
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: citabjockey on July 25, 2011, 09:33:34 AM: Posting pictures would help lots too. A photo of the washer with a
quarter or a nickel in the frame would help us know what you are
talking about. Sounds like a thrust washer from somewhere. Maybe
the clutch, maybe the kickstarter shaft? When you open the cover
you can post pics of that too.

Is it 18 or 19 or 15?
(http://images.powersportsnetwork.com/fiche/images/HONDA/2000/MOTORCYCLES/2264_CLUTCH.gif)

Is it 10 or 9?
(http://images.powersportsnetwork.com/fiche/images/HONDA/2000/MOTORCYCLES/2264_KICK%20STARTER%20SPINDLE.gif)

Good luck!
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 25, 2011, 01:41:42 PM: Quote from: TotalNZ on July 25, 2011, 01:20:12 AM
Hmmm i seem to remember a medium sized washer that dislodged easily out of the powervalve actuator.
Sounds like somewhere in the clutch would be a good start though.

What exactly is the powervalve actuator? (I know, I know, I should have a manual) This washer is about 3/4'' inner diameter, just guessing. I will double check. Thanks for the all the help/troubleshooting but I did not even open the right/clutch side...it has to be something between the left case cover and tranny or somewhere on that side. I have a pretty strong feeling I'm going right back into her even though she sits completely re-assembled, ready to rail....well if I wasn't such a fleatard!

Thanks for the microfiche pic, gave me the idea that I could actually "see" where it may go.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 25, 2011, 01:50:39 PM: Effffffffffer...one thing I can already see I forgot/probly lost....the key in the flywheel shaft. Would that cause the "locking" up problem? Do I still get this souvenir washer? Looking further...
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 25, 2011, 02:50:29 PM: Ok, the clutch pull is from the key not being on the flywheel shaft and it bent the "prong" of the piece that holds the flywheel backing to the motor but also holds the clutch actuator in. It bent off its bottom pin where it sits and allows the clutch actuator to come out farther, so I gotta either bend that back and get a new one.

The washer is 13/16" inside, and about 1 3/16 outside diameter and it looks as though it matches right up with the primary drive bearing. My other friend came over who has a bit of two stroke motor experience and agreed, and it has wear on both the o.d. and i.d. of it, question is when I get back in there what way does the "flat" go. It seems like it would be "key" (haha pun intended for me being a retard) as the flat side has more of a burr on its edges. I cant seem to find it listed on the microfiche though: http://www.cycleworldnj.com/fiche_section_detail.asp (http://www.cycleworldnj.com/fiche_section_detail.asp)

So now I probably need a new key ( I know, I know, a manual) and the pullers again. If the key is less than a week away Im definitely gonna order the flywheel puller and possibly a case splitter...the right tools for the job! Garrrrrrrf I'm going to re-use the gaskets, keep your thoughts on that within your own self.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: eprovenzano on July 26, 2011, 05:50:45 AM: Just mark this down as a learning experience... When I rebuilt my son's Honda 400EX, (yes he's a quad turd) I put 1st hear in backwards. It was rubbing on the case... It split and re-split the case 3 times before a friend on mine found it... I also sheared the flywheel key upon reassembly.... :D
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: citabjockey on July 26, 2011, 07:04:03 AM: When I rebuilt my SC500 I printed copies of all the associated parts explosions of the
engine internals. Then I made index cards and matched the pages with the cards, wrote
the ID numbers of the parts on the page on the cards and put those parts into bags
with the cards. I got a tip from someone else after all of this to put a tie wrap around
sets of washers/cogs/etc with them stacked in the proper order too (something I did
not do but it would have helped). Just a suggestion for next time.

Good Luck with your replit and parts investigation efforts!

I do not see the washer on the CR125 crankshaft page but on older yamaha's there
is a shim on one side of the crankshaft. Does honda put these together with custom
one-off shims too?

(http://i610.photobucket.com/albums/tt188/citabjockey/SC500/IMG_0873.jpg)
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: citabjockey on July 26, 2011, 07:11:21 AM: Missing the key would not prevent it from turning but WILL keep it from running. I think it likely that your hard clutch pull is associated with the "problem" and I also predict that the washer is not the binding issue (but needs to find its home nevertheless). Of course I have been known to be wrong before. Many times. Oh, and your strategy of getting the right tools is spot on. Makes the job much easier.

This is a puzzle. Have fun with it! You will get it. And re-using your new gaskets should be fine if they don't tear on dissassembly.

Quote from: wikid on July 25, 2011, 01:50:39 PM
Effffffffffer...one thing I can already see I forgot/probly lost....the key in the flywheel shaft. Would that cause the "locking" up problem? Do I still get this souvenir washer? Looking further...
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 26, 2011, 01:33:23 PM: Quote from: citabjockey on July 26, 2011, 07:11:21 AM
Missing the key would not prevent it from turning but WILL keep it from running. I think it likely that your hard clutch pull is associated with the "problem" and I also predict that the washer is not the binding issue (but needs to find its home nevertheless).

Quote from: wikid on July 25, 2011, 01:50:39 PM
Effffffffffer...one thing I can already see I forgot/probly lost....the key in the flywheel shaft. Would that cause the "locking" up problem? Do I still get this souvenir washer? Looking further...

Yea I said the flywheel backplate type thing bent when the flywheel "spun off". "Insert Quote
Ok, the clutch pull is from the key not being on the flywheel shaft and it bent the "prong" of the piece that holds the flywheel backing to the motor but also holds the clutch actuator in. It bent off its bottom pin where it sits and allows the clutch actuator to come out farther, so I gotta either bend that back and get a new one"

I hope now that I didnt damage the flywheel, it seems to be the "stuck" part. and I cant tell but I bet its not on so straight anymore. May be even hard to get off being on tittywompiss now!

No one knows where the one washer goes when you pull off the left side cover? I have a good guess, but it's just that. No washers on the microfiche...wtfffffreeeak
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 26, 2011, 02:37:16 PM: Ok I found the key! In the inner part of the flywheel most likely stuck to the magnets in there, thats what caused it to be "stuck". The key stuck on one pack of wires...gorfing them up in the process! Do I need a whole new flywheel or can you just get the magnet/wire part (magneto? stator? whats it called?)? OEM setup was like whooooaaa $400-some, ebay be the best idea?

Gots a while to flip that washer around now. Hello, Eric Gorr......
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: msmola2002 on July 26, 2011, 07:53:59 PM: http://cgi.ebay.com/ebaymotors/New-H-O-OEM-Replacement-Stator-Honda-CR125R-250R-00-01-_W0QQcmdZViewItemQQhashZitem43a893249fQQitemZ290591024287QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_1658wt_803 (http://cgi.ebay.com/ebaymotors/New-H-O-OEM-Replacement-Stator-Honda-CR125R-250R-00-01-_W0QQcmdZViewItemQQhashZitem43a893249fQQitemZ290591024287QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_1658wt_803)

yup, you can get just the stator. A few on evilbay, used ones, new ones, whatever - also find out (read some online oem parts places fiches) and compare part numbers to work out what years have the same P/N and will work. I spent hours at work working out what bits are different on an 02 KX250 and a 99 KX 250 :p

Good luck.
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 29, 2011, 11:28:03 PM: Please tell that you need the flywheel in order for it to kick over "correctly." Please...even if you're lying. I put the washer inside the left case on the main drive shaft....it has to go there, it fits with a pretty tight tolerance...anyway, I put it on the end of the shaft of the main tranny gears, with the flat side so it would be towards the bearing when I put the case back on. Many times while re assembling my scoot I thought of just putting the kickstart on the engine and seeing if it would kick over. But no, not until I put it all back together again did I do that. Again, please tell me that you need a flywheel (which should be in tomorrow) in order for it to kick over smoothly. It sounds like a tranny something or other and kicks hard. I didnt think of even checking it, because I thought I had it right this time for sure, until I was putting the chain back on and I couldnt get a neutral spin goin on. pleeeaase victoria pleeease lie to me!
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on July 29, 2011, 11:52:18 PM: I never thought to look at the tranny section of the microfiche and it looks like I put it in the right spot: http://www.nielsens.com/fiche_section_detail.asp (http://www.nielsens.com/fiche_section_detail.asp) Now I just have to see what size it is
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: ford832 on July 30, 2011, 05:34:49 PM: Quote from: wikid on July 29, 2011, 11:28:03 PM
Please tell that you need the flywheel in order for it to kick over "correctly." Please...even if you're lying.

OK,you need the flywheel on in order for it to kick over correctly. ::) Look on the bright side,every time you tear it apart adds to your knowledge, ;)
Title: Re: 01 CR 125 case split, parts needed to re-assemble?
Post by: wikid on August 02, 2011, 10:23:26 AM: Put the flywheel on and braaaap braaap! But here's me thinking I get to split em again a third time: SHE'S STUCK IN 1ST NOW! haha I rode Sunday, went over the bars beautifully in the whoops, rode again yesterday and stupid me always checking to see what gear I'm in clicks down to 1st and it sticks there. Know what that might be? What parts I need now? Thaaaanks two stroke brethren/sisterns!