883 to 1200

My son and i are in the process of ths converstion.10-1 pistons and a n2 cams.Will this set require rejetting?Any suggestions would appreciated .

Thanks for the reply.She' a 1998

Art will be your man on that model. There are other threads on here on this topic which Art has already chimed in on with some great info.

How do i access the info.

OK I spent the last 20 minutes looking for the old posts. Being as I am at work that may not have been the best thing to be doing LOL but I got paid to do it just the same LOL.

http://bike-talk.com/forum/search.php?searchid=112383

I don't know if that link will work for you or not, if not then go to Pull Up a Chair and Art_NJr has a post there. Click on his name and tell it go to user profile, then click see all posts. Look through those until you see one on the conversion. Art has a lot of posts and I don't know if any pruning has been done to remove the OLD ones yet. If not he will be around soon enough, he digs these Sportster projects LOL.

Good Luck

Thank you for your time and ifo

No problem. Hope you find the help you need in there somewhere. Like I said though if not Art will be around soon. He can give you better help than I can.

Take care now and get some pics posted of this project man. We likes to see too .

Thanks for the kind words y'all - hope I deserve 'em.

I got a message from QuickSand, but evidently there's a problem with direct e-mail communication, so I'll answer the question here as best I can:

Yes, you will have to re-jet (baseline is 42 slow, 175 main), but there's a LOT more to it than that. N2 cams (assuming '91-'03 model Sportster) raise the actual compression because the intake valve closes 3 degrees sooner than stock & "pinging" is a known problem with that combination. What you seem to be doing is targeting the low end of the powerband with 2 things @ the same time & contrary to popular belief, just raising the mechanical compression ratio does not equal more power. I'd need to know more about the specific bike & what it is you want to accomplish to be of more help.

The bike is a 1998 with 1 3/4 drags bone stock.Were trying to accomplish 2 things.We want the bike to come away from red lights and the power to pass when 2 up.(low mileage 11000)
The bike came with 3 exhaust systems.Drags,stock and slip on HD mufflers.
I went back thru your posts lots of good info,the drags will be coming off.So it's stock or mufflers?
We may have jumped the gun again.We purchaced the Harley Performance Stage 1 kit with the EZ mixture?
Please let us know what we need change.Were low budget but we want her right.So were putting on the brakes till we get more info.

Especially for what you're wanting to accomplish, the stock pipes with crossover are the best - the crossover actually does work, it's worth 5-8 HP & even more in the torque dept. As to mufflers, there's a couple great ways to go there, depending on if you want louder or quieter - the older "Screamin' Eagle" slip-ons, Cycle Shack, KromeWerks are all good & although not loud like drag pipes, they're certainly louder than stock - or you can drill the center plate out of stock mufflers with a hole-saw & the bike will sound pretty close to stock, but the flow is a LOT better. And if you want to take the time to do it, you can use a Dremel with cutting & grinding wheels on a flex extension to clean up the ends of the crossover down inside the headpipes. With the SE air-cleaner setup, or other quality aftermarket A/C, the engine will breathe quite well.

I haven't used one off those kits yet, but if you're referring to the one "kenfuzed" sells, it seems to be a good one. The EZ adjust mixture screw is nice, the needle appears to be very similar to the N65C design & from reading about it, it's machined better, so I wouldn't hesitate to use that kit & one of these days I'm going to buy one to play with. Your baseline is 42 slow jet, 175 main & 2.5 turns out on the idle mixture screw. A 170 main sometimes works better in an 883>1200 conversion with stock cams. People tend to drown the engine with a 45 slow & 180 or larger main, but until you get into serious head work, cams, etc., the 42/175 or 170 combo is what you want.

I personally like the stock cams for a street bike, but the N2's do give you more "ooomph" on the low end. However, as I mentioned, they can cause a "pinging" problem with the 10:1 pistons & you'd no doubt need to back off the ignition timing, which tends to be 2-4 degrees fast from the factory. The other thing is if you're keeping the 883 heads stock & using "reverse dome" conversion pistons, the valves are smaller than a 1200 & that setup makes for good low-end power anyway - an 883>1200 will beat a stock 1200 stoplight-to-stoplight. Another factor is the front drive belt sprocket is a 27-tooth on an 883 - it's a 29 on a 1200 & the lower sprocket makes for better takeoff, so you'll want to leave the 27 alone.

The biggest single factor in doing a conversion is getting the cylinders bored/honed on torque plates to match the new pistons *exactly* & do not assume that any kit of cylinders/pistons has been matched because they rarely are. If you're using Wiseco pistons, the recommended piston-to-wall clearance is .0025" & that doesn't mean *somewhere between* .002" & .003". Those pistons "grow" as they heat up, you need the room for them to expand & for example, the PTW clearance with KB pistons is .0015" because they don't grow. A thousandth of an inch may not sound like much, but believe me it is, we measure to the 10-thousandth & I've seen cylinders change shape by as much as .004" from sitting on the workbench to having torque plates bolted on - that might as well be a mile.

Torque plates duplicate the forces put on the cylinders when they're installed on the engine & without them you don't get a true measurement. But any good machine shop will have a set & they're simple to use. Just measure the pistons with a micrometer below the bottom ring groove all the way around, then using the largest measurement (should be in-line with the wrist-pin hole), add the PTW clearance the piston manufacturer recommends & hone the cylinders to that. Do it right the 1st time & you won't have to do it again for @ least 60,000 miles. Don't do it & you'll be rebuilding in 6 months - it is that important.

We thank you for all the info,
We'll get started on the cross overs and exhaust pipes this week end.Monday all the parts are sceduled to arrive.Then were off to check those clearances.
We wish you the very best on the flats
QuickSand and Son