Bike: 2008 SG w/big sucker intake, pcIII, and super trapp se slip ons.

I want to go to a 103 and am interested in low end torque over hp. Street light to street light stuff. My question is, are bigger valves really necessary given I don't want to go to a different exhaust. I do not like loud exhaust and this exhaust is acceptable to me after trying several other slip ons.

 

Were you planning on going with a cam with your 103 setup? If you're not interested in HP, why not just put in a good low end cam.

 

how much do you want to spend on motor upgrades?

 

If you just want to hot rod around town(street light to street light) skip the 103 until you need to look at the top end and just put in Andrews 37 cams and adjustable push rods. Bike will wake up big time, and you will save a bunch of money. Bang for the buck, that is pretty hard to beat!

 

If you are just looking for low end torque...I would go with a cam upgrade first...It may be all you are looking for. There's a lot of good cams to pick. Use the search feature here and pick the cam that suits your need. I will be upgrading to a SE 255 cam...it may not be the best cam out there..but I believe it's good for me.

 

Yes I am going to do a 103 kit with cams, adjustable push rods, etc and some head work. Just not sure if that head work should include bigger valves given my somewhat restrictive exhasut............

 

get a total kit with parts that are proven to compliment with each other--I've had four motors 103, (2)107s and working a project now---for about $110 more you can do a 107 you'll get what your looking for + some. Check out the motorhead section of the forum the information is endless there

 

Lynn gives good advice. Go with recommended packages from a reputable builder. If going to a 103, and a decent cam, you can gain so much addtional from going into the heads and having them done properly.

Too many guys on here put together "science projects" and then wonder why they don't have the rideability that is expected. Not saying that mix and match doesn't work, but you have to know what works with what. You are spending a lot of money, might as well get the most for it !!

 

I guess I'm not phrasing my question correctly so I'll try again.

I plan on a 103 upgrade from one builder using all the matching parts from one vendor.
I'm interested in low end power not high end power and will have a cam that will achieve that.
My exhaust is somewhat restricted so it doesn't flow as well as most after market.
I'm having head work done to match the 103 kit.

My question only has to do whether to include larger valves in the head work. I've gotten two different answers from two different builders, so 'm asking here for any opinions. So far I've gotten a lot of good advice but no one has offered an opinion on the valve question or I'm just not seeing it.

 

Getting a larger intake valve will give you more low end power. Getting headwork done without getting valve work done at the same time is a waste of money in my opinion. The benefits of putting a larger intake valve in, totally eclipses the few extra dollars spent. That's one man's opinion. Do you want to know the benefits?