Another big bore question

I went with the yamahxs650 big bore kit and am very happy with it. Lessened the vibes a significant deal and pulls REALLY well. It’s not going to win any speed awards, but for my little back road racer it does great. I had plans to do a cam, port work and new carbs, but honestly right now it runs so well for me with the tuned carbs that I’m leaving it alone. Whenever I need more work done that may change. Might I also suggest saving up a little money and upgrading your clutch as well?
a clutch upgrade is a must. One point on springs: no need to go Barnett (43% stronger). Very heavy and will actually wear out the clutch actuator nylon bushing. Barnett is what I wanted to get and MMM ar 650central talked me out of it. Sold me Vesrah springs (14% stronger) and EBC fiber plates. No slippage on my 52hp build.
 
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a clutch upgrade is a must. there is a point on springs: no need to go Barnett (43% stronger). very heavy and will actually wear out the clutch actuator nylon bushing. Barnett is what I wanted to get and MMM ar 650central talked me out of it. Sold me Vesrah springs (14% stronger) and EBC fiber plates. No slippage on my 52hp build.
I don’t actually remember if I swapped out springs on this bike or if it was my other one, but I know I added the 8 pack clutch @gggGary put together a while back and once I adjusted it right it’s great. I want to try and get a dyno run this year just to see where I’m at.
 
Here is a suggestion:
Why not develop the motor in stages.
Stage 1 Big bore.
Stage 2 Port job
Stage 3 Cam + springs (good springs are not cheap)

It is not a big job to pull a motor and install a cam.

Artic XS, from my experiments with porting a multi angle seat cut on the exhaust works well but on the inlet it killed flow. I have yet to repeat the test with 2 angle and 3 angle cuts.
That's what I have decided to do I'm ordering the big bore kit today .I will install that this spring and go from there. I would definitely like to install a cam but unless I can just install the one from mikes xs I can't do it at this point
 
ZRX100. I think in reality if Flash was to do the work in stages he would be so impressed of the result with just the big bore he would leave it at that.
What my point was is that its not an all or nothing situation.
Thanks .I gonna try that .I figure even if I at the cam later and do the heads ,I will at least know what each has to offer and be able to speak on it in later conversations.
 
How do you all feel about heiden tuning?
I have a positive impression, I visited the workshop in the Netherlands, and had a chat with Jerry Heiden some 10+ years ago. The parts are pretty much the same as MikesXS though. But they also have some other bits. I bought a set of single wall 40 mm OD SS head pipes that are a close copy of the stock headers, after my "generic" 38 mm single wall headers cracke. I believe these SS pipes were German made.
 
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