con rod

Number of posts : 10 Registration date : 2007-02-19

Hi all,

My students have found a con rod that may be ok for a 175.

info as below:
Conrod-Kit KTM 250 H20
incl. conrod, pin,
bearing upper/lower,
washer disc

High quality spare conrods made by MAZZUCHELLI. Can serve as original replacement or for tuning purposes.

You will find the exact measurement below by using the designation of the letters. In case a letter is NOT listed the respective part is NOT included.

The additive "A" with the article numbers means that the Conrod-Kit with silvered Bearing piston rod is delivered.

Available for almost all current scooter, moped and mokick models.

The Conrod kit includes the following parts:

A: conrod:125mm between centres

B: pin: 22x60mm

C: bearing lower: 22x28x16mm

D: bearing upper: 18x22x25mm

E: washer disc: 22.2x36x1mm

Web site is http://www.sip-scootershop.com/pages/index.php?ID=22931&SETLANG=EN&EXPLODIM=px&_requested_page=%2Fpages%2Fdetails.php

Do you think this rod will work?

Paul Brwon

Subject: conrod sizes Sat Apr 28, 2007 2:48 am

Hi Paul,
Have you checked that the small end size is suitable for the choice of piston and gudgeon pin. It is easy to restrict your choice if you are not careful. Otherwise if you are making your own crank it is best to draw up everything, just to be sure the crank will not end up too wide for the cases.
Good luck.
Alan

Subject: Re: con rod Sat Apr 28, 2007 8:12 am

Hi Paul
that conrod looks is if its the same as the one I am using
Robbie

Subject: Con Rod: the big-end cage...? Sun Apr 29, 2007 2:24 pm

Hi Paul!
This might not be necessary with modern design of bits and pieces - but just in case...
Our first Bantam racer was a 175 competing in 250cc events. Our first and second times out were non-finishes attributable to big-end bearing failures. The phospher-bronze roller cage was too large on its OD causing it rub on the big-end eye, overheat and break up... Quite messy!
All the best... Cheers! JayBee.

Subject: KTM Con Rod Tue May 08, 2007 8:21 pm

I looked on SPI website for Mazzuchelli rod, looks like they do not have any in stock. My local KTM will look for rod if I can tell him which model and year, I suggested KTM 250 and H20..... drew a blank. Does anyone know which model these rods fit ?
Robbie, where do you get yours from ?
...or should I get radical, lower the top of crankcases and use a 116mm Bultaco or 110mm RD400 rod, getting close to the ideal 2:1 rod length/stroke ratio. Should it rev easier or will I loose botton end torque ?