Opinions on my cylinder

Got questions? We got answers....
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

[img][/img[IMG]http://i1149.photobucket.com/albums/o593/98rebuild/DF42FC7F-8BCF-4014-8CF4-618BCEA74579_zpsbkpuzyyh.jpg[/img]]

Trying to figure out posting pics. This is just one. I have more but just making sure this works first. It's a 98 kdx200
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

Ok. It looks like the link is working so....
Hi everyone! Love this place. This is my first post. So, I'm doing a frame up build on this 98 kdx200. The bike was in rough shape but started good. Needed almost everything. So that's what I'm doing. The only thing I don't want to do is send my cylinder out if I don't have to. I can't afford it right now considering I'm almost in this for $1500 already. I have no history on this bike at all. I cleaned the piston off to see if it was stock. I think it is. One ring is right at the service limit and one is just under the service limit. Doing a new piston obviously but my question is do you guys think the rings are worn or the cylinder. I can't bring it anywhere to get checked. So how does this cylinder look?? Please keep in mind the lighting in the pics. There are no scratches, nothing I can feel with my fingernails. Right at the top there is a slight edge but not much at all. Can I slap a piston in and rip!!!!?
User avatar
doakley
Gold Member
Gold Member
Posts: 1241
Joined: 02:58 pm Mar 10 2016
Country:

Re: Opinions on my cylinder

Post by doakley »

Can you measure the bore?
If not I'd probably put in a new piston, rings, top bearing and clips, reassemble and check compression. If good, ride it! Oh, check the ring end gap before assembly.
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Re: Opinions on my cylinder

Post by 98rebuild »

No I can't check the bore. I wish I could. I just hope when I check the end gap with new rings it's in spec.
I'm hoping the rings are just worn out. If I absolutely have to I'll send it in. Just trying to see what some people think of the condition of the bore. I think it looks ok but there are people here with more experience then me. I do plan to check compression. Thank you. I appreciate the response. I would love more opinions guys and gals.
User avatar
SS109
KDXRider.net
KDXRider.net
Posts: 5770
Joined: 05:11 am Aug 23 2009
Country: USA
Location: Tucson, AZ, USA
Contact:

Opinions on my cylinder

Post by SS109 »

Can't see your pic. Try any image hosting other than photobucket. Imgur, Flickr, etc.
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Opinions on my cylinder

Post by KDXGarage »

here ya go
Attachments
F824B425-3369-4241-9503-072CF3954DEC_zpsmxu5lr34.jpg
F824B425-3369-4241-9503-072CF3954DEC_zpsmxu5lr34.jpg (156.2 KiB) Viewed 16697 times
F810E084-C2C1-4EAD-87B7-69FBA617F086_zpscdml40wc.jpg
F810E084-C2C1-4EAD-87B7-69FBA617F086_zpscdml40wc.jpg (136.29 KiB) Viewed 16697 times
F1AD3096-3194-4E26-8C63-F8C381D06456_zpsxhd9pxdx.jpg
F1AD3096-3194-4E26-8C63-F8C381D06456_zpsxhd9pxdx.jpg (152.41 KiB) Viewed 16697 times
DF42FC7F-8BCF-4014-8CF4-618BCEA74579_zpsbkpuzyyh.jpg
DF42FC7F-8BCF-4014-8CF4-618BCEA74579_zpsbkpuzyyh.jpg (155.92 KiB) Viewed 16697 times
D3164312-6676-48FE-ACCF-988018FD04F2_zpsboa38qpn.jpg
D3164312-6676-48FE-ACCF-988018FD04F2_zpsboa38qpn.jpg (153.38 KiB) Viewed 16697 times
CC8A935B-8F94-4BF2-A065-71A9AFCC105F_zps14pextmf.jpg
CC8A935B-8F94-4BF2-A065-71A9AFCC105F_zps14pextmf.jpg (119.76 KiB) Viewed 16697 times
BB45944E-00FA-4637-A9A7-BAB33CBB89AC_zps93vbtz0f.jpg
BB45944E-00FA-4637-A9A7-BAB33CBB89AC_zps93vbtz0f.jpg (156.51 KiB) Viewed 16697 times
7409758D-A258-475B-A3F8-2B44047E5EA7_zpsmst7yzsm.jpg
7409758D-A258-475B-A3F8-2B44047E5EA7_zpsmst7yzsm.jpg (164.23 KiB) Viewed 16697 times
1715E715-E0EA-480D-BC40-CF0FC857D159_zpslaw4bcaz.jpg
1715E715-E0EA-480D-BC40-CF0FC857D159_zpslaw4bcaz.jpg (165.63 KiB) Viewed 16697 times
2A514405-FEBE-4528-BBE5-FC4DDD1CD5BB_zps1bkf6kwk.jpg
2A514405-FEBE-4528-BBE5-FC4DDD1CD5BB_zps1bkf6kwk.jpg (160.85 KiB) Viewed 16697 times
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Opinions on my cylinder

Post by KDXGarage »

That last one does not look good to me. :hmm:
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
User avatar
SS109
KDXRider.net
KDXRider.net
Posts: 5770
Joined: 05:11 am Aug 23 2009
Country: USA
Location: Tucson, AZ, USA
Contact:

Opinions on my cylinder

Post by SS109 »

That looks like it needs to be replated badly IMO.
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
sthutch
Supporting Member II
Supporting Member II
Posts: 134
Joined: 07:00 pm Sep 27 2009
Country: USA
Location: Michigan

Re: Opinions on my cylinder

Post by sthutch »

I agree, replate.


Sent from my iPhone using Tapatalk
Sthutch

1st Bike: '72 Arctic Cat Whisker (rode it to the wheels fell off)
2nd Bike: '76 KT250 Trials (gone, but not forgotten)
3rd Bike: '01 KDX200
4th Bike: '96 DS80 (okay, my 9yr old's and it's gone)
5th Bike: '04 RM65 (okay, he's now 10 and it's gone)
6th Bike: '08 KTM 105xc (okay, he's now 13)
7th Bike: '06 KTM 200xc-w (okay, he's now 16)
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Opinions on my cylinder

Post by KDXGarage »

" I can't afford it right now considering I'm almost in this for $1500 already."

May I ask what other repairs or modifications you had previously made? Thank you.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

Sure. I personally haven't done any mods to the bike. The reason it's getting expensive is because it needs a lot of parts. Bearings, kick shaft, kick spring, kick lever, tires, bars. The list goes on and on. But it ran good. There is no scratching or gouging. Nothing you can feel anyway. The mods it had when I got it. The air box lid has holes drilled and it has a full FMF system. That's it. Stock jetting was in it. Like I said the rings are right at the service limit. Just under actually. So I'm hoping with the new rings it in spec. If the cylinder is in spec, wouldn't it be ok to run then? I really appreciate all your opinions. Thank you
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

I'm getting all my parts before I start to reassemble the bike. The motor is almost done. All that's left is the top end. It's just a bare frame right now. Was green but is now silver. Parts add up fast! Needs new forks also. When I took them off I noticed they were bent. Plus springs cuz I'm 240lbs. Everything is getting something. Master cylinders getting rebuild kits. Carb kit, petcock. But.. adds up fast! I don't want to send the cylinder off. I will if I have to but.. I'm gonna see what the ring gap is with new rings first.
pumpguy
Gold Member
Gold Member
Posts: 821
Joined: 10:00 am May 29 2012
Country:
Location: Spring Grove, Illinois

Opinions on my cylinder

Post by pumpguy »

I've certainly seen worse pistons and cylinder bores. IIWIYS, I would scotchbrite scrub the bore, put a new set of rings on the existing piston, assemble the top end and do a compression test. If compression is within the specified limits of 95 - 151 PSI, go ahead and run it.

New rings are cheap, and if the gaps are between .006 - .013", the cylinder bore wear is acceptable. The ring gap should be checked at several places in the bore.

The proof is in the pudding. If the bike's performance was okay before you tore it down, or if it's okay after you just put the new rings in it, then go ahead and ride it. You can always do a re-plate and new piston later if and when it really needs it.
User avatar
Julien D
KDXRider.net
KDXRider.net
Posts: 5858
Joined: 07:53 pm Nov 07 2008
Country: USA
Contact:

Re: Opinions on my cylinder

Post by Julien D »

I agree with pumpguy. Except that I would go ahead and replace the piston since you already have it out and it does look pretty beat. Scrub it clean with scotchbrite and WD-40, pop in a piston and rings, test it, and if it's good run it. It's a 200, so you'll be okay with the less expensive pro-x piston rather than having to go with a forged unit. Just make sure you replace that C with another C. The pro-x pistons come in incremental oversize to accommodate slight differences in factory bore.
Image
david
Member
Posts: 524
Joined: 08:30 pm Oct 10 2011
Country:
Location: Forney, TX

Re: Opinions on my cylinder

Post by david »

http://www.wiseco.com/ProductSearch.aspx

They appear to be out of stock of the 'C' piston, but have 'B' & 'D'. You could probably find the 'C' (01.4285.C) on ebay, and cheaper than list price.

http://www.ebay.com/itm/ProX-Piston-Kit ... 8L&vxp=mtr
'81 KDX 175
'90 KDX 200
'07 Vulcan 2000 Classic LT (totaled 4/25/15)
'82 Honda GL500 (sold)
'96 ZXi 1100 JetSki
'98 STX 1100 JetSki
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

Oh, deff a new piston. I have no idea how old that one is. Was gonna go with the weisco kit just cuz it's already in the budget. But ya maybe a prox that's one size over will work too. Not sure yet. Where should I start when I'm ready to assemble the bike. Motor in frame and then the swing arm or....? Shock, radiators? My first complete assembly. It sure is fun though! Thank you guys so much for you thoughts! I'm hoping to pass on some knowledge when I'm completely done. Oh just thought of a question. I'm not going to run the odometer, so that cable will not be there but I should be able to use that odometer wheel spacer without the cable connected right? I know there's some after market spacers out there but I'll just use this if I can.
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

Thank you for the link on the piston!
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

Once I get new rings and take the measurements I'll know what has to be done. If I need to send it out I will. I'm running this kdx no matter what! I've come to far now!!
98rebuild
Member
Posts: 9
Joined: 09:23 pm Aug 20 2017
Country: Usa

Opinions on my cylinder

Post by 98rebuild »

When can I do a compression test. I was thinking I had to have the motor in the bike with the carb and plug in there. Kick lever on. Is there a way to bench compression test?
david
Member
Posts: 524
Joined: 08:30 pm Oct 10 2011
Country:
Location: Forney, TX

Opinions on my cylinder

Post by david »

98rebuild wrote:When can I do a compression test. I was thinking I had to have the motor in the bike with the carb and plug in there. Kick lever on. Is there a way to bench compression test?
It would be pretty hard to do a compression test on the bench.
'81 KDX 175
'90 KDX 200
'07 Vulcan 2000 Classic LT (totaled 4/25/15)
'82 Honda GL500 (sold)
'96 ZXi 1100 JetSki
'98 STX 1100 JetSki
Post Reply