I hope to do my conversion this winter, I am about to purchase a set of screamin eagle 10/1 comp conversion pistons and black cylinders off of a private buyer. Not sure what else to do. What I really need to know is what kind of head work should I get. Not going for high horse, but I dont want the engine to be out of breath before it is done revving. Has anyone just enlarged there valves in there 883 heads without porting, and if so how effective are they?

picowatt,

Make sure that your Pistons and Jugs are Matched!!! Nallins does great work on heads for about $800.00 mild setup, your heads. Might be worth checking out!!:D

When I did my 1200 conversion I just wanted the heads cleaned up. I went to my local HD shop and they gave me the number of the guy they send work to. He said he had to replace the exhaust valves and the only ones in stock at HD were the 2004 bigger ones. Whatever, I said. So I got, bigger exhaust valves new valve guides and seals and he machined all the black crap off the inside. Cost me $180, $60 of that was the price of the new valves. I wish I would have had some money left over to re-powerder coat to heads. I didn't think of that when I was planning for the job. The machining kinda XLFXLFXLFXLFXLFXLFXLFXLF 'em up.

I've done the SE 10:1 conversion, SE 1200 cylinders, SE bolt in cams, and have never been happier. The heads are untouched. I ended up with upper 70's power figures. The whole conversion as I did it cost me $834.00 and once the old posts are brought into the new forum, I will direct you to a link with the dyno results.

Several others on the forum have done the exact same conversion and are equally as pleased. And yet others have done the conversion minus cams and seem happy as well.

Since you are buying the pistons and jugs second hand, make sure to check for proper fit and cylinder wear. Keep inmind that most dealers will knock 20% off the parts needed for the conversion if you push them a little bit.

PM me and I will email my dyno sheet directly to you if you would rather not wait for the old data to be merged.

I used Wiseco 9,5:1 complete kit and it went on like a charm just added a James top end gasket set.
Too cold now to ride so I have to wait until spring to test her properly.
I just have 50 km on the meter and it is "break in driving"
Extremely hard not to twist the throttle as I can feel the extra power. :cry1
I´ll let you know in april

I plan to do same as You with Wiseco's

Hi,
Last year I added the 10:1 conversion pistons and 1200 HD barrels.
Conversion made a good deal of power over the 883. Different bike.

I wish now I had fitted bigger inlet valves (1200 has bigger valves) and had heads ported at the same time...then I would not have to do that when I fit the N4 cams I have laying around....So, get the heads done at the same time.

Whiffy

Whiffy,

You wouldn't have to have the 1200 valves installed in the 883 heads to run that cam. I run the SE bolt incams (which is a very similar grind to the N4's) and it performs rather well. As a matter of fact, do you (or anyone else with the 10:1 conversion pistons/883 heads/stock cams) have a dyno? I could overlay a stock cam dyno onto several SE cam dynos from different bikes. This would give everyone an idea of exactly how the cam change would effect performance on these 883 headed 1200's.

I talked to Headquarters about porting my heads and adding bigger valves, and they said the SE 1200 conversion piston is dished and I'd need to replace them with flattop pistons in order for the port and new valves to be of any value. Something to do with compression and all that. And then, even then, I'd get about 10 HP increase.

Not worth it. The port and new valves alone would cost around $700.

Shu,
I have a dyno sheet of an 883>1200 with 10:1 dishtop Wiseco's, stock heads and cams lying around somewhere. Problem is, I don't have a scanner. Can I FAX them to you? Feel free to PM me.

Jdt...that is an example of what these forums are for. You now want more power and your first build is not done in such a way that the next step is simply adding more stuff. You would have to toss the pistons...thats a waste. I did the same...the first 1200 conversion was back when they used flat tops, but ground out the heads . Now they leave the heads alone and the pistons are dished. Now you have the wrong pistons for future upgrades and I had hogged out heads that were no good for further work. I have to say, still, go for the good heads with new pistons. Those pistons you have must be so easy to sell as they are hugely popular...
When my first conversion @ 65 hp was changed ,just by adding HQ heads to my flat tops... I GAINED 13 HP!...and those heads were so good that, that they didnt need to be replced even with future building till the engine was doing 120 hp.
Heads IMO are the biggest building block..... like lego...the heads are that big flat piece ya start with to add all the other blocks to.

Narley,

What kind of head work did you have done?

Narley,

What kind of head work did you have done?

detailed here.
http://www.head-quarters.com/html/mild.html
here is the before and after dyno

http://www.head-quarters.com/html/78___76.html

Narly,

Nice Numbers!!

I talked to a local Indy here in San Antonio and he sends his heads to Branch in Calif. have you heard of, or anybody here ever have any work done by them?? This Indy says he can get 80+ horses out of my motor with his heads, HD Jugs, J&E pistons, HD bolt in Cams, and BUB 2-2 pipes??
Sound reasonable??

I got 84hp with factory pistons, N2's, headwork and cycle shacks. Save the money from pistons and bubs for heads. Bubs look nice but you can't beat the price/cost/performance factor of cycle shacks.

barry,

Is there much gain or loss between the cycle shack's and the SEII that I already have.. I've also thought about the V&H short shots!!

From what I hear Cycle Shacks are the best 2 into 2 exhaust available as far as hp AND tq are concerned. They work very well and the sound is awesome. I switched from D&D slip-ons( great for HP but not for Tq ) to these and am very happy. If I had the cash though I would probably get a thunderheader.

I have to say, still, go for the good heads with new pistons. Those pistons you have must be so easy to sell as they are hugely popular...


Ah, I am not going to do it. I was exploring my options. I have no intention of plunking down another $700-900 on my Sportster. It runs pretty good as is. I've got 5K on my conversion now, will probably put another 5 on it and get it dyno'ed again. I bet I am running about 75 HP now, which is plenty good.

I got a set of Santee mufflers and they sound great.
Same pricerange as Cycle Shack
Not as loud as Cycle Shack I´m told, is that correct?

I plan to do same as You with Wiseco's

Just do it. I got my stuff from a dealer in texas

Swede,
what is in that complete kit you bought? How much You pay for?

Swede

Where in Texas did you get your Stuff!!!

ok so the private buyer I was going to buy the parts from fell through. Now I have to Figure out where I am going to get them. I have been thinking of Nallins, but still want to see all the options. Spending 800 dollars on head work is way out of my price. I was just thinking about getting there big valve treatment if anything. Getting the heads worked and flowed wont happen until I hit a small lottery or next winter. This winter is just for conversion.

I think your back to Shu's conversion. I did the cams and no matter what anyone says california bikes need new cams. There was a thread somewhere where about some outfit in NY I think where the guy uses the dished pistons and flows the 883 heads for some outragous numbers. But again, all head work is espensive.

Since the private buyer fell through, I have been looking at my other options. Of course money is a big factor, Tuition takes most of it, and food the rest. Whatever is left I can put into the bike. I am debating on Vtwin manufacturings conversion kits. The indy shop here said he can get them for me at $450.00. Now I am not sure whether to go with the 10:1 or 9.5:1 comp ratio.

The total parts list for the engine wiill probably be, SE intake, I will do the carbs, Stock heads, again either 10:1 or 9.5:1 conversion pistons and cyclinders, and bassani pro street pipes baffles in.
I do plan on doing more work to it, but that will not be until next year.

Any info on the different comp ratios would be a help.

I recommend that if you do a simple 1200 conversion with the 883 heads and keep the stock cams, then stick with 9.5:1 compression reverse dome conversion pistons becasue the 10:1 pistons would have a greater chance of pinging. If you do go with the 10:1 pistons, then it'll take a little extra fine tuning in the carb and timing but it is possible.

Thanks thats what I thought. Ideally I would like to get the 10:1 pistons and the TC88 igniton from TwinTec, but again money is a huge issue. Do you happen to know how big a difference there would be between the two different pistons sets. Probably not much for theseat of the pants I am guessing, but I ahve never done it.

Also, If I happen to get some more money saved up, should I go with heads or cams, I know for a fact I wont be able to do both???
What kind of cams to go with"? Looking for torque and ridability, I am not changing the redline

Heads work will give you the biggest bang for your buck, but it is more expensive than cams.

First of all, forget the ignition change on this type on conversion as it is wasted money.

Cams will give you about 5 to 7 hp. If you are leaning toward head work, then ditch the conversion style pistons and slap in some flat tops and have the heads mated to them and completely reflowed. Just sticking in larger valves and a little port work isn't going to get you that much (and if done wrong may not get you squat) and is going to be somewhat expensive.

From a cost vs. increased in performance, the 1200 kit is the best. After that, you are looking at costs increasing at an increasing rate compared to cost.

To explain: You can do a simple 10:1 compression 1200 conversion with SE bolt in cams for right at $800.00. It'll give you 70 to 75 hp and have a power band in the 2000 to 6000 rpm range. OR you could go with a known builders kit (Nallin or Zippers, etc) for about $1500 to the skys the limit for anywhere from 80 to 120+ hp.

Since money is tight for you and you sound like you are looking for the best bang for the buck out of your 1200 conversion, I'd say either do the simple 9.5:1 conversion with stock cams (mid 60's hp) or the 10:1 conversion with SE cams (mid 70's hp) and wouldn't bother with the heads unless they have a lot of hard miles on them.

Swede

Where in Texas did you get your Stuff!!!

From Sorgys scooter supply
www.sorgys.com
It´s located in Red Rock i think

Swede,
what is in that complete kit you bought? How much You pay for?

Don´t remember but abt 400€ including a james gasket kit, all shipped to sweden.
Call Sorgy and tell him you want what I got,
Ola from sweden. I´m sure he remembers me

Shu,

When doing the H-D 1200 conversion can you use the flat-top pistons instead of the dished and then do head work later??

Hi,
If you do a conversion with flat top pistons, instead of the dished pistons you will end up with a very high compression without the headwork to reshape the combustion chamber, thats why we have dished pistons....

Now I suppose you could run the engine with flat tops with the standard 883 combustion chamber, but not domed pistons. You would need to make sure the valves have enough clearance on the flat top pistons valve pockets (always good to check this anyway) and correct piston-head squish clearance as well.

I'm not sure what compression you would be running, but over 10:1 is a guess..perhaps closer to 12:1 which is rather high for a road petrol burning engine. Pinking would be almost certain with pump gas.

I have the dished pistons and no headwork with 10:1 compression. The power increase was just what I needed for a road bike. I still had to retard the ignition by around 5 degrees to stop pinking when the engine got hot this summer, so I'd guess there would be just too much compression with flat tops...

My 2 pence

Whiffy

whiffy

Thanks for the info!! I thought that going to the flat tops would be to much, but wasn't sure!! :D