Planet Minis

firepower354 · 08-01-2009, 05:57 AM

Just a heads-up that I'll have the first 118cc kit done this week, or shortly after.
80 cylinder sleeved for a 58mm bore, high compression piston, and a rebuilt crank with a 3mm longer rod. Gets rid of the crazy tall stock piston, and we clean the sling (it needs it) while the crank's apart. Better rod/stroke ratio is an added plus. Case boring is required. Full-flow oil mod can/should be done while the cases are apart. I also have trick in-line oil filters to protect your expensive investment.

I'll soon be adding these items to my site, along with plenty of "regular" goodies for the Upright Citizens

gman · 08-01-2009, 07:10 AM

Strokers? 3mm offset pin available for the stock XR 80 rod? 134 kit would be sweet!

Compression ratio, Opitions?

How many chip$ ?

I just pick up 2 basket case 80 engines

firepower354 · 08-01-2009, 01:14 PM

I haven't sourced an offset pin in the smaller 23mm 80 size. Yet. Lots of area machine shops sitting idle.

Compression ratio: high, but no final number. Gonna be in the 12-13 range, with the current slug. I'll do a duffer flatty later, for 11:1.

Crank rebuild and rod swap, sleeve, install sleeve, piston kit, case boring, oil mod, filter should be about $350-ish. Your cases, crank and jug are needed, or pay a core charge for my parts.

Brach19 · 08-01-2009, 03:03 PM

do you have anything for the old xr75? I have a 1974 that i want to go big with but my options are pretty limited.

firepower354 · 08-01-2009, 08:01 PM

Quote:

Originally Posted by Brach19

do you have anything for the old xr75? I have a 1974 that i want to go big with but my options are pretty limited.

Yep

The stock jug won't take as big a sleeve, but if you're OK with using an 80 jug, we can get you in to 118cc.

ZBguyohio · 08-02-2009, 10:12 AM

Quote:

Originally Posted by Brach19

do you have anything for the old xr75? I have a 1974 that i want to go big with but my options are pretty limited.

Motorcycle parts, motor mounts, and racing pipes. Whittier, CA

I just ordered a Swing Arm for an Early XR from them. He has some cool stuff.

Tony

ZBguyohio · 08-02-2009, 10:16 AM

Quote:

Originally Posted by firepower354

Yep

The stock jug won't take as big a sleeve, but if you're OK with using an 80 jug, we can get you in to 118cc.

Tell me more about what your doing with the XR. I know the newer xr stuff like the piston is taller. How are going to make it work with the stroker ? Keep us posted please.

Tony

Brach19 · 08-02-2009, 07:07 PM

Quote:

Originally Posted by firepower354

Yep

The stock jug won't take as big a sleeve, but if you're OK with using an 80 jug, we can get you in to 118cc.

isn't the xr80 stud pattern different than the xr75?

Jthomas7 · 08-03-2009, 06:42 PM

Correct me if I'm wront but the 73 - 76 XR75 and the 77-78 have a different stud pattern? For some reason I'm thinking that.

firepower354 · 08-03-2009, 09:07 PM

Hmmm. I dunno. I thought it was just the stud diameter, but I forget stuff.

Brach19 · 08-03-2009, 10:24 PM

can you do anything with the stock xr75 jug?

Jthomas7 · 08-04-2009, 03:24 PM

Guess I need to get an engine out there to you and do a review on the vintage minis site.

firepower354 · 08-04-2009, 09:17 PM

Quote:

Originally Posted by Jthomas7

Correct me if I'm wront but the 73 - 76 XR75 and the 77-78 have a different stud pattern? For some reason I'm thinking that.

You aren't. I just went to the shop and looked. Right front stud is farther to the rear than on later ones. Others looked close, but I was using a used base gasket as a guide. 72cc early jug will go 50mm, but should be able to be sleeved for some more bore. I can do some measuring...

Jthomas7 · 08-04-2009, 09:46 PM

also the left middle stud on the newer ones doesn't go all the way to the top of the head, and does on the older ones I believe.

ZBguyohio · 08-05-2009, 03:47 PM

Let me ask this. The 4 speed pistons and rings a long gone. What other honda piston works, if any ? Maybe a 2 cylinder bike ? I have a 50mm Venola Piston for a 4 speed that is 10.5 to 1. If i remember it brings it to 90cc and 120 with stroker crank. It uses CT-90 ring set. Lets keep this thread going. I wish we could get our own spot on here for XR-75s. I suggested it never happened.

Tony

sdg1 · 08-06-2009, 02:18 AM

wow dude sound sweet

firepower354 · 08-06-2009, 06:20 AM

Quote:

Originally Posted by ZBguyohio

Let me ask this. The 4 speed pistons and rings a long gone. What other honda piston works, if any ? Maybe a 2 cylinder bike ? I have a 50mm Venola Piston for a 4 speed that is 10.5 to 1. If i remember it brings it to 90cc and 120 with stroker crank. It uses CT-90 ring set. Lets keep this thread going. I wish we could get our own spot on here for XR-75s. I suggested it never happened.

Tony

Can you take some measurements from that Venolia? Might help in sourcing a cheaper option. Pin to top edge, dome height will work.

08-01-2009, 05:57 AM	#1 (permalink)
firepower354 Advertiser Join Date: Oct 2006 Location: Flint MI Posts: 10,989 My Mood:	XR80 Bigger Bore Kit Just a heads-up that I'll have the first 118cc kit done this week, or shortly after. 80 cylinder sleeved for a 58mm bore, high compression piston, and a rebuilt crank with a 3mm longer rod. Gets rid of the crazy tall stock piston, and we clean the sling (it needs it) while the crank's apart. Better rod/stroke ratio is an added plus. Case boring is required. Full-flow oil mod can/should be done while the cases are apart. I also have trick in-line oil filters to protect your expensive investment. I'll soon be adding these items to my site, along with plenty of "regular" goodies for the Upright Citizens __________________ If it has my name on it I did it;) FirepowerMinis.com Custom FPM parts and engines. Parts and service for all makes. Honda Trail Bikes parts and accessories. Pitster/Piranha/Thumpstar bikes, parts, engines and accessories.

08-01-2009, 07:10 AM	#2 (permalink)
gman 1st Gear Member Join Date: Apr 2008 Location: Pittsfield, Massachusetts Posts: 240	Re: XR80 Bigger Bore Kit Strokers? 3mm offset pin available for the stock XR 80 rod? 134 kit would be sweet! Compression ratio, Opitions? How many chip$ ? I just pick up 2 basket case 80 engines

08-01-2009, 01:14 PM	#3 (permalink)
firepower354 Advertiser Join Date: Oct 2006 Location: Flint MI Posts: 10,989 My Mood:	Re: XR80 Bigger Bore Kit I haven't sourced an offset pin in the smaller 23mm 80 size. Yet. Lots of area machine shops sitting idle. Compression ratio: high, but no final number. Gonna be in the 12-13 range, with the current slug. I'll do a duffer flatty later, for 11:1. Crank rebuild and rod swap, sleeve, install sleeve, piston kit, case boring, oil mod, filter should be about $350-ish. Your cases, crank and jug are needed, or pay a core charge for my parts. __________________ If it has my name on it I did it;) FirepowerMinis.com Custom FPM parts and engines. Parts and service for all makes. Honda Trail Bikes parts and accessories. Pitster/Piranha/Thumpstar bikes, parts, engines and accessories.

08-01-2009, 03:03 PM	#4 (permalink)
Brach19 1st Gear Member Join Date: Aug 2007 Location: rosamond, CA Posts: 119	Re: XR80 Bigger Bore Kit do you have anything for the old xr75? I have a 1974 that i want to go big with but my options are pretty limited.

08-03-2009, 06:42 PM	#9 (permalink)
Jthomas7 2nd Gear Member Join Date: Dec 2005 Location: Ponca City, Oklahoma Posts: 804	Re: XR80 Bigger Bore Kit Correct me if I'm wront but the 73 - 76 XR75 and the 77-78 have a different stud pattern? For some reason I'm thinking that.

08-03-2009, 09:07 PM	#10 (permalink)
firepower354 Advertiser Join Date: Oct 2006 Location: Flint MI Posts: 10,989 My Mood:	Re: XR80 Bigger Bore Kit Hmmm. I dunno. I thought it was just the stud diameter, but I forget stuff. __________________ If it has my name on it I did it;) FirepowerMinis.com Custom FPM parts and engines. Parts and service for all makes. Honda Trail Bikes parts and accessories. Pitster/Piranha/Thumpstar bikes, parts, engines and accessories.

08-03-2009, 10:24 PM	#11 (permalink)
Brach19 1st Gear Member Join Date: Aug 2007 Location: rosamond, CA Posts: 119	Re: XR80 Bigger Bore Kit can you do anything with the stock xr75 jug?

08-04-2009, 03:24 PM	#12 (permalink)
Jthomas7 2nd Gear Member Join Date: Dec 2005 Location: Ponca City, Oklahoma Posts: 804	Re: XR80 Bigger Bore Kit Guess I need to get an engine out there to you and do a review on the vintage minis site.

08-04-2009, 09:46 PM	#14 (permalink)
Jthomas7 2nd Gear Member Join Date: Dec 2005 Location: Ponca City, Oklahoma Posts: 804	Re: XR80 Bigger Bore Kit also the left middle stud on the newer ones doesn't go all the way to the top of the head, and does on the older ones I believe.

08-05-2009, 03:47 PM	#15 (permalink)
ZBguyohio PM Newbie Join Date: Jun 2008 Posts: 45 My Mood:	Re: XR80 Bigger Bore Kit Let me ask this. The 4 speed pistons and rings a long gone. What other honda piston works, if any ? Maybe a 2 cylinder bike ? I have a 50mm Venola Piston for a 4 speed that is 10.5 to 1. If i remember it brings it to 90cc and 120 with stroker crank. It uses CT-90 ring set. Lets keep this thread going. I wish we could get our own spot on here for XR-75s. I suggested it never happened. Tony

08-06-2009, 02:18 AM	#16 (permalink)
sdg1 PM Newbie Join Date: Jul 2009 Posts: 56	Re: XR80 Bigger Bore Kit wow dude sound sweet

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