question for people who have a 1250 kits
Road Captain
Joined: Jul 2006
Posts: 656
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RE: question for people who have a 1250 kits
I did my 1250 with the cyclinder/piston kit from NHRS. They're a great shop for cylinder/piston kits for all years, but stay away from headwork from them if your bike is an 04' or later, they've had may issues with oil consumption, but other than that they're great, freindly service. As for numbers......I could care less about a dyno numbers...........I can definately say it's got a hell of a lot more grunt than before. I even had to put a stronger clutch kit in to handle the power, i had pretty bad acceleration slippage after the conversion. What's really gonna make a difference in power is going to be all the additional mods you do on top of the basic 1250 like headwork, ignition, air intake, cams. I would suggest taking a look at the xlforum site, they have a section dedicated to conversions, although sponsored by nhrs, there's also a lot of guys that have done conversions from other shops.
Road Warrior
Joined: Jun 2005
Posts: 1,334
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RE: question for people who have a 1250 kits
Be careful with NRHS 1250 kits. They used to do great work, but recently it has went downhill. Any reason you want a 1250 specifically? Doing a 1200 buell conversion tends to work great.
If you go with an iron-lined 1250 cylinder from NRHS it is just a V-twin Manufacturing 1200 cylinder (made in Taiwan) bored to 1250cc's. They claim it has a thicker liner than stock and thus why it's possible. The stock 1200 cylinder can only be bored to 1223cc's. That doesn't sound right to me, but I don't know enough about it to say one way or the other. The cast iron cylinders are Axtell.
If you go with an iron-lined 1250 cylinder from NRHS it is just a V-twin Manufacturing 1200 cylinder (made in Taiwan) bored to 1250cc's. They claim it has a thicker liner than stock and thus why it's possible. The stock 1200 cylinder can only be bored to 1223cc's. That doesn't sound right to me, but I don't know enough about it to say one way or the other. The cast iron cylinders are Axtell.
Club Member
Joined: May 2006
Posts: 10,815
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From: Virginia
RE: question for people who have a 1250 kits
I disagree about the problem lying exclusivelyin the headwork from NRHS. I had 1250 cylinders and pistons from NRHS installed and used about 1 quart of oil every 500 miles. The heads and cams were stock and i had no problem with oil use before this. The heads had new valve seals put in and still had the same problem.
Another guy on here and the XL Forum had the same 1250 kit put on his and he also ket the stock heads and cams. He ended up having the same problem as me. He took the 1250 cylinders and pistons out and replaced them with the stock 883 components and his oil usage went back to normal.
If I were you and had a 04 or newer Sporty I would stay away from the NRHS conversion and go with someone else just to avoid having to go through this.
Another guy on here and the XL Forum had the same 1250 kit put on his and he also ket the stock heads and cams. He ended up having the same problem as me. He took the 1250 cylinders and pistons out and replaced them with the stock 883 components and his oil usage went back to normal.
If I were you and had a 04 or newer Sporty I would stay away from the NRHS conversion and go with someone else just to avoid having to go through this.
Road Warrior
Joined: Jun 2005
Posts: 1,334
Likes: 2
RE: question for people who have a 1250 kits
It's not just 04+ anymore. Recently someone had headwork done from them that was put on a 2002 bike. After 12K mi. the valves had excessive carbon build-up (oil being burned by entering through the valvetrain). Dan said that 12K mi. is what you would expect out of a set of their heads. I think it all boils down to **** poor machining and quality control. One person thought he was buying a kit with 10.5:1 compression, but it ended up being much closer to 11.0:1 compression (pretty radical since he lived in Texas).
Road Warrior
Joined: Jun 2005
Posts: 1,334
Likes: 2
RE: question for people who have a 1250 kits
What I call the buell conversion puts a buell top end on a sportster. I recommend keeping the components matched. So if you want to do a thunderstorm buell conversion you would buy thunderstorm heads, pistons, and .497 cams. If you want to do a XB buell conversion you would buy XB heads (come stock on 04+ 1200 sportster), pistons (04+ Sportster can just use a thiner head gasket), and .551 cams. I have seen this work very well and produce 90 rwhp on sportsters. The valvetrain will last much longer than NRHS's 12K mi. claim.
You will also need a way to adjust the timing for the new cams to get the most out of that combination and a 2-1 or 2-1-2 exhaust (haven't seen one made for sportsters) to get the most of that combination. However, the right 2-2 can achieve almost the same peak power.
You will also need a way to adjust the timing for the new cams to get the most out of that combination and a 2-1 or 2-1-2 exhaust (haven't seen one made for sportsters) to get the most of that combination. However, the right 2-2 can achieve almost the same peak power.
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Cruiser
Joined: Feb 2007
Posts: 237
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RE: question for people who have a 1250 kits
How about jugs? I have an 883.
Thanks for the input
Thanks for the input
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Road Warrior
Joined: Jun 2005
Posts: 1,334
Likes: 2
RE: question for people who have a 1250 kits
You can bore out your 883 jugs to 1200cc's to fit a std size buell piston. The alternative is to buy 1200 cc cylinders to fit a buell piston. Personally, I would just use the 883 cylinders. The only difference between 883 and 1200 cylinders is 883 cylinders have a thicker liner. In addition, if the cylinders have something like 10K mi. on them, then by that point you have the advantage of additional stability (they are very unlikely to warp compared to a new cylinder).
Road Master
Joined: May 2006
Posts: 1,133
Likes: 6
From: Londonderry, NH
RE: question for people who have a 1250 kits
i am currently having a 1200 upgrade done to my 06 883L. I am having a local indie do the work as they do exceptional work and have treated me very very well since day 1.
I am having the very basic bread and butter upgrade done, using allharley parts (screaming eagle i think). They are boring out my jugs, new pistons, rings, gaskets, etc... They PROMISE me that there will be no oil consumption issues or any reliability issues..and I trust them. The owners both used to be service department managers at manchester hd, and still have an excellent relationship with the dealership.. In fact, most of their business comes from recommendations from this particular dealership.
I am glad that i have read about the issues with nrhs as I was very tempted to go with their kit. I would urge others that have 04's and up to stay away as well. The last thing I want is problems that didn't exist before. I have about 7 thousand miles on my bike and she's treated me like gold up to this point. I don't want to sacrifice any reliability for performance sake. I will let you all know how my upgrade works out.. unfortunately, probably not till april!! damn snow.
rob
I am having the very basic bread and butter upgrade done, using allharley parts (screaming eagle i think). They are boring out my jugs, new pistons, rings, gaskets, etc... They PROMISE me that there will be no oil consumption issues or any reliability issues..and I trust them. The owners both used to be service department managers at manchester hd, and still have an excellent relationship with the dealership.. In fact, most of their business comes from recommendations from this particular dealership.
I am glad that i have read about the issues with nrhs as I was very tempted to go with their kit. I would urge others that have 04's and up to stay away as well. The last thing I want is problems that didn't exist before. I have about 7 thousand miles on my bike and she's treated me like gold up to this point. I don't want to sacrifice any reliability for performance sake. I will let you all know how my upgrade works out.. unfortunately, probably not till april!! damn snow.
rob