TOPIC:

Hem... have I done some stupid?

I overhaul almost my whole bike and want a bike I can trust (starting when I need it), I can have short and long trip and don`t need to be afrid someting goes wrong.....

+0.25mm VS +3.00mm .....

From what all you have replay to me will the overbore set to 810 give me more nm and not peak power.
Normal I only need to-do small re-jetting and nothing else, use original ignition and keep the rest of the engine original,
the valve will be overhauled.

Things I need to be aware of is over heating or hard throttling....

Normal I run the bike nice and are not hard to it, I don`t run to the limit, but its nice to have some extra power available when you need to overtake a car etc in a hill.

I can add I`m living in Norway and a normal summer is between 59-77 degrees Fahrenheit.

How can I avoid overheat? have a eye on the temp and run it nice when its hot?
I was thinking replace the oil filling cap with a temperature meter?

If I got problem with heat I can install oil cooler ? but it shall not be necessary?

I will not be able to re boor the cylinder? so It will be nice to get a spare barrel to have just in case?

But I understand I can expect these setup shall work for almost the same time as original stock pistons, I take care of the engine?

What about the brakes and the frame construction? My frame is a 650 SR European model with disc brake front (double) and single disc brake rear, I have understand my bike is identical to a 750 when it comes to brakes / frames / etc.. so the bike itself
shall handle 750 stock engine, since Kawa using the same part for 750?

If the jetting is correct you will not have over heating issue's with that piston kit.
At one time Wiseco made an 830 cc kit and they had over heating issue's on the street.

Why would a big bore piston engine run hotter than a regular engine if both were going down the road at the same speed? I understand that the big bore engine will have more potential for power, but if the rider is keeping the same speed, thus the same power being generated (big bore engine can get by with a smaller throttle setting), there shouldn't be much if any difference in heat unless I'm missing something.

Glad to see you went with the 810 and the better quality Wiesco's. I kick myself almost every day for not going that way when I re did mine...... Even have a 750 block but was too chicken to open up the cases to have them bored (you don't need to with the 750 motor). With your cooler weather I wouldn't worry a bit on over heating....... out west its like a oven and Zukdave and many others are doing fine.

Thank you all for feedback.
Looking forward to test these out

1.
Is there something special I need to inform the engine workshop with?
Clearances they shall make for the pistons?

www.wiseco.com/ProductDetail.aspx?ItemID...Year=1981&AppID=6904

2.
What is the best way monitor for over heating?

90% sure when APE Race parts did my pistons they were done at .002 clearance....... I told them I wanted them done at the min clearance they would recommend......... but since I'm not 100% sure or they might go a little different on the 810 kit I'd ask them.

The paper work with the Wiseco kit will have info on piston clearance and ring end gap.
If the shop doing the work is worth a shit they'll know how to do it.

The pistons should come with this.
Steve

I picked up the pistons today, will deliver them to workshop next week.

I found papers inside each piston explain the clearness for the piston rings, red paper as SWest gave me below.

1. What about the clearness between the liners / cylinder walls and the piston, should that be 0,051mm, please see attached photo?
2. Is there more I need to inform the workshop of, is it a special hone I shall use or something?

Ok looks like my memory of .002 was right........ (anyone else like to confirm this) ........one thing is when you get the block back wash it with soap and water then scrub the walls down with wd40 and clean paper towels till they come out spot less........ had to go over mine maybe 3 or 4 times till I got all the honing grit off.

Take the pistons to the shop doing the bore work and let them do their job stop over complicating things
looking for the perfect answer.

I've done five over bored motors this past year and not one time did I have to tell the mechine shop how to do thier job.

Hehe thank you for your replays

I’m a person who want to understand / learn, so I wouldent “micro controlled” the work shop,. Always nice to understand what they do, they normal work with cars and tractor pulling engines.

I will deliver the piston next week, looking forward to get the piston and head back