<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">It doesn't have to, the spacers just need to keep the rods from moving too far. They can be pretty loose, certainly looser than thrust bearing clearance. Still, I think it would work a lot better to put spacers in the pistons where the movement is relatively slow rocking rather than spinning. That's what we came up with for racing two stokes--no reason why it couldn't work here as well. I discussed that with Uncle Jack, but nothing came of it. <div><br><div><div>On Sep 12, 2008, at 8:06 AM, <a href="mailto:fubog1@aol.com">fubog1@aol.com</a> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Two questions actually...<br>1) the spacers on the pin... does this not induce side thrust loads on <br>the piston? This is not good.<br>2) if the BE is narrower, there is excessive cheek clearance. Again, a <br>bad thing.<br>I'm curious as to how this works in service...?<br>Glen<br><br><br>-----Original Message-----<br>From: Larry Young <<a href="mailto:cartravel@pobox.com">cartravel@pobox.com</a>><br>To: Greg Solow <<a href="mailto:gregmogdoc@surfnetusa.com">gregmogdoc@surfnetusa.com</a>><br>Cc: FOT <<a href="mailto:fot@autox.team.net">fot@autox.team.net</a>><br>Sent: Fri, 12 Sep 2008 9:47 am<br>Subject: Re: [Fot] TR Racing cranks<br><br><br><br><br><br>Greg,<br><br>To get a larger radius on the crankpins, do you weld the edges and then<br>regrind? On my current engine, I welded the edges of the crankpins to<br>reduce their width so they would accommodate chevy rods. I them<br>reground with a larger radius to reduce the stress riser. This is a<br>cheap approach that addresses both weaknesses, rods and cranks. Others<br>on the list have used chevy or other commodity rods, but have used<br>spacers at the wrist pin to center the rod. The only problem is that<br>welding puts a lot of stresses in the crank and proper nitriding<br>requires stress relieving. The grinder had a hard time getting it<br>straight. He said it was out 0.022 the first time it came out of the<br>oven.<br><br>Larry Young<br><br><br><br>Greg Solow wrote:<br><br><br><br><br><br> A good used crank properly race<br>prepared, deep case nitrided and ground with the proper radii on the<br>journals, is very reliable at power outputs of up to 16<br>5 hp as long as<br>the revs are kept below 6800 rpm. The weak link in bottom end is the<br>connecting rod. For use over 6,000 rpm they need to be replaced with<br>steel billet rods.<br> <br> Greg Solow<br> _______________________________________________<br><a href="http://www.team.net/donate.html">http://www.team.net/donate.html</a><br><br>Fot mailing list<br>Fot@autox.team.net<br>http://autox.team.net/mailman/listinfo/fot<br><br><br><br>_______________________________________________<br>http://www.team.net/donate.html<br><br>Fot mailing list<br>Fot@autox.team.net<br>http://autox.team.net/mailman/listinfo/fot<br><br></div></blockquote></div><br><div apple-content-edited="true"> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><span class="Apple-style-span" style="color: rgb(118, 15, 79); font-size: 16px; ">Bill Babcock</span></div><div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Babcock & Jenkins</div><div><a href="mailto:Billb@bnj.com">Billb@bnj.com</a></div><div>503.936.7660</div><div><a href="http://www.bnj.com">www.bnj.com</a></div><div><br class="webkit-block-placeholder"></div><div><div><font class="Apple-style-span" color="#010000">Editor</font></div><div><font class="Apple-style-span" color="#010000">Ke Nalu e-Magazine</font></div><div><font class="Apple-style-span" color="#010000"><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; "><i>Paddlesurfing's Web Journal</i></span></font></font></div><div><font class="Apple-style-span" color="#010000" size="3"><span class="Apple-style-span" style="font-size: 12px; "><i><br class="webkit-block-placeholder"></i></span></font></div><div><a href="mailto:Bill@kenalu.com">Bill@kenalu.com</a></div><div><a href="http://www.kenalu.com">www.kenalu.com</a></div><div>blog: <a href="http://www.ponohouse.com/ponoblog">www.ponohouse.com/ponoblog</a></div></div></div></div></div></div></span></div></span></div></span> </div><br></div></body></html>