I have a chance to pick up a set of 1200 cylinders cheepo and have a few questions. I would like to change to 1200 heads but money being tight i would like to wait to do that. I would also like to find a set of buell heads if i can.
do i need to use conversion pistons if i don't change the heads right away? Is there a difference between the pistons for use with 883, 1200, or buel heads?
I know carb and cam issues will have to be dealt with as i make these changes, but my main concern right now is piston fit. Any info appreciated.
North,
Your 1200 cylinders has a larger bore then the 883, hence you need larger pistons & rings to fit.
You can't just install 1200 jugs and say I'll do the rest later.
With one advancement others follow.
Buy the jugs now if the're a good price, but know full well you will need other parts later.
Hope this answers your main question.
Panzer
thanks panzer.. I know i need new pistons to fit. my question is this... does the heads i am using have any impact (other than compression ratio) on the pistons i buy? I would like to set it up for the 1200 heads but run the 883 heads till i get the heads, then change them out
i guess i am wondering if there would be nay clearence problems etc.
Yes, depending on the heads you are going to use, you will use different pistions.
The XB heads, for example, use flat-top pistons.
What year is your bike? I have a set of used 883-1200 heads that I would sell cheap. They are 883 heads that were relieved for a 1200 conversion I did several years ago, very common to do before, and they use flat-top pistons too. I ran them for several years and took them off when I upgraded to the XB heads.
99 xl. I might be interested in the heads.. tell me what has been done to them?
Can you bore to 1200 and still use stock 883 heads? I apoligize if this has already been answered.
northbrun,
There are several ways to do the 883-1200 conversion. With regards to cylinders, you can either bore the stock 883 ones or buy new 1200 ones. With regards to heads and pistons here are some common options:
- modified 883 heads (combustion relieved), standard flat-top 1200 pistons
- unmodified 883 heads, reverse domed pistons
- Buell Thunderstorm heads, domed Thunderstorm pistons
- Buell XB heads, standard flat-top 1200 pistons
If you use 883 heads you must bring the compression down, either by relieving the heads (enlarging chamber) or using reverse domed pistons. Back in the days, I think relieving the heads was the most common method - and that is the route I took when I converted my 1993 XL to a 1200 in the mid-90s.
Then, Buell came out with new heads, first the Lightning and then the Thunderstorm heads and in particular the Thunderstorm heads became very popular to use when doing a 883-1200 conversion. And still is. The Thunderstorm heads require you to use a domed piston though.
Then, Buell came out with the XB heads which in many's judgement are the best heads. And with the XB heads you use standard flat-top 1200 pistons.
Perhaps the cheapest way to go is to use your stock 883 heads and get reverse-dome pistons. It might not be the ultimate performance buster (compared to using Thunderstorm or XB heads), but it is a huge kick compared to an 883.
The heads I have are the stock 883 that have been relieved so they are used with standard flat-top 1200 pistons. I ran them for several years on my XL and took them off when I did a top-end rebuild and got XB heads.
By the way - the above is for pre-rubbermounted XLs. I haven't really followed the changes for the rubbermounted Sportys and whether the conversion options still apply.
I converted my 02 883 to 1200 using KB pistons, reverse dome, and keeping the standard heads......ran sweet and I wish I still had it in my shed, you wont be disappointed at the performance for the dollar.