pistons

[andy mac]

looking 4 pistons for an rs 14mm wristpin can anyone help
i know they arnt made anymore
has anyone used the wisico ones r they any good
any ideas

[parillaguy]

There are a few original new old stock RS125 + RS250 pistons still around (same pistons) and a guy in California who had some pistons made by Wiseco. I have two of his custom made Wiseco pistons and they look pretty good. parillaguy http://www.tz250racing.com/iB_html/non-cgi/emoticons/biggrin.gif

[SVRGP]

I have two on Ebay right now. They are the Wiseco pistons.

[andy mac]

has any body used the wisico pistons how do they perform compared to honda

[sbrokerboy]

I have the 13100-NF4-020 pre 93 250/ pre 95 rs125 pistons, I have the pistons, bearings, and pins, NO RINGS All brand new $60, gets cheaper if you buy 5 or more.

[JZcolor]

I've been curious about the wiseco piston as well.
A forged piston ,though very tough, expands differently than a cast piston and can be prone to cold seizure. I've read references to this fact on some of the other sites. It's usually mentioned in passing rather than a first hand account so it's still kinda grey to me.
I've used wiseco pistons in an Aprilia RS250 with no issues but the bike uses a thermostat and the bike was thoroughly warmed up prior to blasting. It's no GP bike but we ran them HARD

"A" pistons might become a commodity soon and it would be nice to have a few sources

I've decided I'm going to run a thermostat in the 125 as I have had some success in the 250. Especially in the spring /fall where daily temps can swing some 20-25 degrees. Just seems more consistant for setup and I would'nt run the forged piston without a thermostat. It's gonna provide a more stable Temp base around the cylinder.

Grab Strokeroy's and SVRGP's extras in the meantime....

[SVRGP]

I have ran the wiseco pistons in my 91 RS250 and 87RS250 with no problems. I do make sure the motor is nice and warm. I have sold these pistons to some people asking them to give me a reply on what they think about them. I have no replies yet. My self I have had no problems with the pistons.

[andy mac]

i must admit id prefer to use hrc pistons because u know where u r with them; but if i cant get them i would use wisco
sbokerboys pistons 13100 nf4 020 can 13121 nx4 811 be used with them
thanks andy

[SVRGP]

NX4 i think have a 15mm wrist pin. NF4 are 14mm.

[andy mac]

sorry what i ment to say can i use nx4-811 rings in a nf4 020 piston

[andy mac]

hi im still trying to find out what piston rings i would need to use with 13100 nf4 020 pistons
thanks andy http://www.tz250racing.com/iB_html/non-cgi/emoticons/rock.gif

[SVRGP]

I have a NF4 ring and NX5 ring a can't tell the difference. I measured the thickness of the ring and it was the same. I hope that helps.

[yammit]

There are a few original new old stock RS125 + RS250 pistons still around (same pistons) and a guy in California who had some pistons made by Wiseco. I have two of his custom made Wiseco pistons and they look pretty good. parillaguy http://www.tz250racing.com/iB_html/non-cgi/emoticons/biggrin.gif
does anyone know if wiseco make a piston for the 86 rs 250 Honda 56x50.6 not the 54x54 87 onwards.

Thanks
John.

[SVRGP]

The closes piston I see in my book from Wiseco would be a 79 CR125 piston. The wrist pin in your 86 is 14mm right? If so this piston might work if the pin is at the right height from the top of the head of the piston. I hope that helps.

[yammit]

The closes piston I see in my book from Wiseco would be a 79 CR125 piston. The wrist pin in your 86 is 14mm right? If so this piston might work if the pin is at the right height from the top of the head of the piston. I hope that helps.
Thanks the CR 125 piston is the right bore and the pin is at the
correct height and some guys are using them here but they
have to be modified at the skirt and the cutaway requires a lot
of alteration I have not tried it yet as I have 4 new old stock
pistons and a few used but usable ones but there are three of us
running 85/86 models and wqe are all getting low on pistons
and looking for a source of honda ones or a replacement .
http://s107.photobucket.com/albums....250.jpg (http://s107.photobucket.com/albums/m318/yammit/?action=view&current=86rs250.jpg)
86rs250.jpg
Thanks again for the reply.
John.
http://img134.imageshack.us/img134/5707/th86rs250mc9.jpg (http://img134.imageshack.us/my.php?image=th86rs250mc9.jpg)

[gzinga]

Hey guys,

which wiseco pistons for a 1991 RS 250? wiseco PN?

thanks!!

[fredybender]

After a bit of research, here is what comes up for me and RS250RF:

79' Stock CR125 pistons are discontinued; No stock in USA, nor Canada...

Wiseco, makes a standard 56mm piston replacement from the 79' CR125, P/N 430M05600

Going for about 96$ US (no pin or ring included)
Pin P/N CW14
ring 2205CDM

Two things:
These still have to have the skirts machined
I do not know the reliability, considering the heat expansion might be different than original Honda's 13100-ND4-700 & 701

I think I will buy two, and have them machined at a friends shop...

Will keep you posted; If this works, I suggest That we could look at a group buy set up;

Just a Question:
Who is running on cylinders that run on 131000-ND4-700 & 701 pistons?

Who would be in?

Not saying I can get this done for shure, but I'm serious about these pistons (weak point of my project right now, and looking to change that...)

[2stsmoke]

Pistons have a taper.How are you going to machine them?. http://www.tz250racing.com/iB_html/non-cgi/emoticons/rock.gif

[fredybender]

Pistons have a taper.How are you going to machine them?. http://www.tz250racing.com/iB_html/non-cgi/emoticons/rock.gif
Depending on what machine you use, and what amount of material needs to be removed...

If its just skirt material removal, there will not be enough pressure to move them out of a jig (pie jaws in a chuck) especially being aluminum; And you can use a smaller diameter tool to reduce pressure even more...

I have a few friends with Multi-task machines, also known as mill turn machines (Integrex, DMG, and a few others...)

Has anyone here done this, and could someone chime in as some of the details of the modifications?

[yammit]

Pistons have a taper.How are you going to machine them?. http://www.tz250racing.com/iB_html/non-cgi/emoticons/rock.gif
Depending on what machine you use, and what amount of material needs to be removed...

If its just skirt material removal, there will not be enough pressure to move them out of a jig (pie jaws in a chuck) especially being aluminum; And you can use a smaller diameter tool to reduce pressure even more...

I have a few friends with Multi-task machines, also known as mill turn machines (Integrex, DMG, and a few others...)

Has anyone here done this, and could someone chime in as some of the details of the modifications?
I have a friend who has done the machining on the cr 125 pistons
and has used them quite successfully I will contact him and ask
him to post details here so far I am sure of interest in around
40 pistons and still working on it . as I will have an ornamental
86 model soon as we have onlt two new pistons left.

Yammit.

http://www.tz250racing.com/iB_html/non-cgi/emoticons/biggrin.gif http://www.tz250racing.com/iB_html/non-cgi/emoticons/biggrin.gif http://www.tz250racing.com/iB_html/non-cgi/emoticons/biggrin.gif

[SVRGP]

I was looking into making a new run of pistons for 87-92 Rs 250. The kit will come with piston, ring, pin, and cir clips. The price will be $150 for the kit. I like to get 20 per sold to make the run of 50 so there will be more in the future. If anyone is interested you can email me at sjspagel@sbcglobal.net. ("sjspagel@sbcglobal.net.) Thanks

[parillaguy]

New RS250 pistons (HRC originals as well as Wiseco replacements) for the 1987-1992 RS250s will fit 1987-1994 RS125 Hondas as well. http://www.tz250racing.com/iB_html/non-cgi/emoticons/biggrin.gif

[gzinga]

Yoh ALL....I just got an email from Steve RSCycles that there are few 14mm piston pin coming in....I don't need them but if you do....you gotta jump on it....

Gabe