S & S Cycles 750 and 865 Big Bore kits for the 650 twins.

Ace

Well travelled
Location
E TN, USA
Yes, they called the Connie a 700, but they called it a 700.
The Interceptor was called a 750, but was actually 736. Stroked.

There should be enough power in the new twins for sidecar use. Big bore kit would be even better.
I meant to say the Connie was called 700, but actually was a 692.
 

Black Campbell

Getting there...
I can comment on the 650 cam and hi-compression piston set up. We threw those in with S&S pipes and a K&N air filter with DNA airbox eliminator when I got my Interceptor back in January.

I don't know what I was thinking: I never mod engines, just cosmetic stuff, but stock it was faster off the line than my Triumph Street Cup 900 (great gearing) but could only just touch the ton here at a mile up in elevation. The S&S literature, what little there is, made this seem fairly straightforward an upgrade; it's not.

The initial issues were detonation under heavy throttle (about 4k and above). Timing for the new cam was off significantly from stock. We fixed that and she was fine except once the engine warmed up or the weather was hot. Again, detonation at heavy throttle at 4.5-5k in higher gears. I suspected the Euro5 emasculation all bikes have to suffer through -- she's just too lean with the higher compression. That said, she was pulling 115mph on a flat road into a good 30 knot wind, but sounded like she was going to fly apart. She also was smoking my buddy's Continental light to light. Even with the issues, I could feel the bike wanted to go faster. (I suspect what I wanted was to recreate the performance of my '10 Thruxton, which could hit 122 reliably. The Interceptor easily beats the acceleration of that bike, and is close on top end.)

We tried a booster plug to sort it, but that cause the detonation to worsen and drop to 3k. (So, yes, booster plugs do something...just not what I needed.) This confirmed to my mechanic it was a fueling issue. We threw in a Power Commander V two weeks ago and took it to a face team with a dyno in a nearby town and threre she sat for two weeks. The O2 sensors were an issues and required bungs welded in to get the sensors positioned for a good read. They had to tweak the fueling as much as 50% in spots! These things are way too lean, even stock. (Though I do like the 70ish MPG I was getting.)

Got it back this afternoon and it's good! The dyno had her pear at 49.25hp at the wheel (at a mile up), and torque comes in and stays most of the power band at a hair over 42ft/lbs. She pulls strongly now from stoplight to 6.5k. I got her up to 80mph coming home on the highway very quickly.

If you decided to do this particular set-up, Motopia New Mexico has the map they built for this particular set-up.
 

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supercub

Getting there...
Location
Old Saybrook, CT
Looks like you have to change the cylinder sleeves, are they pressed in?
The sleeve fit to the cylinder bore has to be a tight tolerance to allow the interchange. The resultant piston to wall clearance is dependent on the fit.
How much HP gain can be had by going up 100cc with ecu tuning?
 

Eatmore Mudd

Moderator
Staff member
Looks like you have to change the cylinder sleeves, are they pressed in?
The sleeve fit to the cylinder bore has to be a tight tolerance to allow the interchange. The resultant piston to wall clearance is dependent on the fit.
How much HP gain can be had by going up 100cc with ecu tuning?
I don't remember if the 750 sleeves need the cylinder block to be bored or if it's the 865 sleeves or both. I do remember that in one case ( maybe both?) after removing the factory sleeve the cyl block is bored with a .005 taper to it, heated in an oven, sleeves inserted an a pleasure plate applied to the top to keep the sleeves from creeping up as it cools.
 

Yogi

Getting there...
Location
The Swamp
I can comment on the 650 cam and hi-compression piston set up. We threw those in with S&S pipes and a K&N air filter with DNA airbox eliminator when I got my Interceptor back in January.

I don't know what I was thinking: I never mod engines, just cosmetic stuff, but stock it was faster off the line than my Triumph Street Cup 900 (great gearing) but could only just touch the ton here at a mile up in elevation. The S&S literature, what little there is, made this seem fairly straightforward an upgrade; it's not.

The initial issues were detonation under heavy throttle (about 4k and above). Timing for the new cam was off significantly from stock. We fixed that and she was fine except once the engine warmed up or the weather was hot. Again, detonation at heavy throttle at 4.5-5k in higher gears. I suspected the Euro5 emasculation all bikes have to suffer through -- she's just too lean with the higher compression. That said, she was pulling 115mph on a flat road into a good 30 knot wind, but sounded like she was going to fly apart. She also was smoking my buddy's Continental light to light. Even with the issues, I could feel the bike wanted to go faster. (I suspect what I wanted was to recreate the performance of my '10 Thruxton, which could hit 122 reliably. The Interceptor easily beats the acceleration of that bike, and is close on top end.)

We tried a booster plug to sort it, but that cause the detonation to worsen and drop to 3k. (So, yes, booster plugs do something...just not what I needed.) This confirmed to my mechanic it was a fueling issue. We threw in a Power Commander V two weeks ago and took it to a face team with a dyno in a nearby town and threre she sat for two weeks. The O2 sensors were an issues and required bungs welded in to get the sensors positioned for a good read. They had to tweak the fueling as much as 50% in spots! These things are way too lean, even stock. (Though I do like the 70ish MPG I was getting.)

Got it back this afternoon and it's good! The dyno had her pear at 49.25hp at the wheel (at a mile up), and torque comes in and stays most of the power band at a hair over 42ft/lbs. She pulls strongly now from stoplight to 6.5k. I got her up to 80mph coming home on the highway very quickly.

If you decided to do this particular set-up, Motopia New Mexico has the map they built for this particular set-up.
Thanks for the report.

I have added a DNA filter, Verex open exhaust pipes, and S&S mufflers to my Interceptor. The weight savings, sound, and general ability to breathe better have made my bike so much more fun to ride. I have already purchased a S&S cam and high compression pistons. I plan to keep displacement at 650cc . Did you install the S&S reinforced connecting rods while in the motor ? I have also considered doing the clutch. However, I'm not sure if S&S is still making their version of the beefed up clutch for the INT 650, although I think Revelry cycles down under does. It sounds like a Power Commander V and solid tuning are absolutely nessential . One thing leads to another , LOL

Again thanks for the report, I am eager to learn more.
 

supercub

Getting there...
Location
Old Saybrook, CT
My Honda CB160 sleeves are s slip fit inside of the cylinder. From reading posts about the setup, Honda had to pick and match sleeves to the cylinders to keep the correct clearances for proper fits, or else the piston to cylinder clearance would be off. I tried swapping but the small difference was noticed right away.
 

DaveinHutto

Getting there...
Location
Hutto, Texas
The Interceptor and Continental are designed to keep the aftermarket busy. It starts with one little thing and like a snow ball rolling downhill, next thing you know its out of control! I needed the bars another inch up and the footpegs down and back. then it was panniers and the new seat. Looking at the new headers and cans. cam and pistons? probably. Change the gearing for west Texas, yep.
 

Black Campbell

Getting there...
Thanks for the report.

I have added a DNA filter, Verex open exhaust pipes, and S&S mufflers to my Interceptor. The weight savings, sound, and general ability to breathe better have made my bike so much more fun to ride. I have already purchased a S&S cam and high compression pistons. I plan to keep displacement at 650cc . Did you install the S&S reinforced connecting rods while in the motor ? I have also considered doing the
clutch. However, I'm not sure if S&S is still making their version of the beefed up clutch for the INT 650, although I think Revelry cycles down under does. It sounds like a Power Commander V and solid tuning are absolutely nessential . One thing leads to another , LOL

Again thanks for the report, I am eager to learn more.
It dodn't do the rods and over a year haven't had any issues, other than the occasional detonation if she's running hot and getting pushed hard. She is really fuel finicky, now. 91 octane -- or higher, if you don't live in NM. Since then, I've taken her up to top speed once or twice. Best I've got was 125 indicated, and my speedo's off about 3-4% so call it 115-177 actual. She's very torquey now, a d sails up to the ton in fifth without much effort.

my buddy's Continental, however, with the TEC 2-inti-1 lost enough weight that he's been able to hang with me up to 110-115 now that his motor is broken in.
 

JBacklund

Well travelled
It's all relative, but that's a lot of engine work and expense to make my Interceptor a little faster than my W800, and a lot slower than my Thruxton R. Regardless, I wish the RE modders well, of course.
 

BenVoiles

Total noob
Location
Alabama, USA
I know I had a 750 kit in my Yamaha twin with high compression and it ran great. Now people are punching them out alot bigger but apparently there are overheating problems with the bigger bores. Haven't heard of any problems like this with the REs. So I'm just wondering, why would anybody get a 750 kit?
 

Laserman

Well travelled
Staff member
I know I had a 750 kit in my Yamaha twin with high compression and it ran great. Now people are punching them out alot bigger but apparently there are overheating problems with the bigger bores. Haven't heard of any problems like this with the REs. So I'm just wondering, why would anybody get a 750 kit?
Royal Enfield builds their engines around the 1HP+1ft-lbs/1ci range, which is a happy place for making decent power and not stressing the engine much. It's also where it starts to get tougher to make more horsepower unless you're revving the heck out of your engine or adding boost while meeting government-mandated emissions. 1/1 leaves a lot on the table yet exceeding it by too much (sans boost) will sacrifice low-end torque. Yamaha and other Japanese engine manufacturers have much experience exceeding 2HP/ci on naturally aspirated street engines, but they can grenade spectacularly when pushed much outside the carefully crafted OE design parameters. Still, many Japanese things are overbuilt: I recall the 94 Integra GSX-R's transmission could handle up to 700HP lol

I spose the 750 kit would be nice for displacement-limited class racing or perhaps road taxes in some country that might cane people. Because we all know, the 650 twins are a shade under 40ci and put down roughly 42RWHP from the factory. a 750 kit would be a shade under 46ci while the 865 is just under 53ci. That's either 48+ or 55+HP for the same price. With mods there could easily be a 10+HP difference between the 750 and 865. That extra power could make all the difference in requiring suspension and braking upgrades to handle the speed. The 865 isn't necessarily the "smarter" choice unless you have a prescription for Fukitol. Then it's a no-brainer.

Here's the 'big bore kit' I bought for my 650 Interceptor for when I want more speed and acceleration than the damn thing has in stock form... definitely a pricey solution, but works great!
Yeah, the Rocket 3 is an impressive machine. About 4lbs per HP(!) which is roughly double the power of a maxed out 865'd Int/Conti. Anything that bests 10lbs/HP is PDFQ to me!

Think about me laughing at you next time you need to make a U-turn on that longpig tho :D
 

JBacklund

Well travelled
Think about me laughing at you next time you need to make a U-turn on that longpig tho :D
If I think there might be any heavy U-turn work to be done, I usually bring out this sweet little 54 inch Italian...when it comes to tight maneuverability, it even makes my Interceptor 650 feel like a pig.
6729
 
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Andy131

Well travelled
Location
Manchester UK
With regards to Lasermans comments about the cubic capacity / horsepower limits of various countries.
The Inter makes 35kW or 47bhp in real money - this is the limit for A2 bikes that can be ridden by 19 year olds in the UK, so it does seem a deliberate power target.
 

NJ Mike

Total noob
Location
NJ, USA
It dodn't do the rods and over a year haven't had any issues, other than the occasional detonation if she's running hot and getting pushed hard. She is really fuel finicky, now. 91 octane -- or higher, if you don't live in NM. Since then, I've taken her up to top speed once or twice. Best I've got was 125 indicated, and my speedo's off about 3-4% so call it 115-177 actual. She's very torquey now, a d sails up to the ton in fifth without much effort.

my buddy's Continental, however, with the TEC 2-inti-1 lost enough weight that he's been able to hang with me up to 110-115 now that his motor is broken in.
The Power Commander is pretty useless with tuning the bike with any engine work. I too did the 650 high compression pistons, Kent cam, Hitchcocks headers, S&S cans, DNA filter, air injection delete, and with the PC it detonated like yours. I was running premium fuel, 93 octane, and it was only better with non-ethanol 90 octane.

My dyno tuner was able to crack the ECU, and in doing so he could do things that the PC cannot do, like change the ignition timing, and a few other parameters. He got the A/F mixture spot on, and was also able to tune each cylinder separately. It's super smooth now, doesn't ping, pulls like gangbusters, and returns 60 mpg all day long no matter how hard I flog it, and boy do I flog it.
I can comment on the 650 cam and hi-compression piston set up. We threw those in with S&S pipes and a K&N air filter with DNA airbox eliminator when I got my Interceptor back in January.

I don't know what I was thinking: I never mod engines, just cosmetic stuff, but stock it was faster off the line than my Triumph Street Cup 900 (great gearing) but could only just touch the ton here at a mile up in elevation. The S&S literature, what little there is, made this seem fairly straightforward an upgrade; it's not.

The initial issues were detonation under heavy throttle (about 4k and above). Timing for the new cam was off significantly from stock. We fixed that and she was fine except once the engine warmed up or the weather was hot. Again, detonation at heavy throttle at 4.5-5k in higher gears. I suspected the Euro5 emasculation all bikes have to suffer through -- she's just too lean with the higher compression. That said, she was pulling 115mph on a flat road into a good 30 knot wind, but sounded like she was going to fly apart. She also was smoking my buddy's Continental light to light. Even with the issues, I could feel the bike wanted to go faster. (I suspect what I wanted was to recreate the performance of my '10 Thruxton, which could hit 122 reliably. The Interceptor easily beats the acceleration of that bike, and is close on top end.)

We tried a booster plug to sort it, but that cause the detonation to worsen and drop to 3k. (So, yes, booster plugs do something...just not what I needed.) This confirmed to my mechanic it was a fueling issue. We threw in a Power Commander V two weeks ago and took it to a face team with a dyno in a nearby town and threre she sat for two weeks. The O2 sensors were an issues and required bungs welded in to get the sensors positioned for a good read. They had to tweak the fueling as much as 50% in spots! These things are way too lean, even stock. (Though I do like the 70ish MPG I was getting.)

Got it back this afternoon and it's good! The dyno had her pear at 49.25hp at the wheel (at a mile up), and torque comes in and stays most of the power band at a hair over 42ft/lbs. She pulls strongly now from stoplight to 6.5k. I got her up to 80mph coming home on the highway very quickly.

If you decided to do this particular set-up, Motopia New Mexico has the map they built for this particular set-up.
The Power Commander is pretty useless with tuning the bike with any engine work. I too did the 650 high compression pistons, Kent cam, Hitchcocks headers, S&S cans, DNA filter, air injection delete, and with the PC it detonated like yours. I was running premium fuel, 93 octane, and it was only better with non-ethanol 90 octane.

My dyno tuner was able to crack the ECU, and in doing so he could do things that the PC cannot do, like change the ignition timing, and a few other parameters. He got the A/F mixture spot on, and was also able to tune each cylinder separately. It's super smooth now, doesn't ping, pulls like gangbusters, and returns 60 mpg all day long no matter how hard I flog it, and boy do I flog it. And I'm making just shy of 60 hp!

MP RE.PNG
 
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