837cc Big Bore Kit

from across the pond though..

http://www.tts-performance.com/catalog/pro...products_id=472

VFR800 98-01 837cc Big Bore Kit

£400.00

H0839

JE Pistons supply the highest quality forged pistons on the market. Most of our kits come complete with Pistons, Pins, Circlips and Rings. Standard bore piston kits do not come with piston rings. At TTS we can bore your cylinders, fit sleeves if required, bore and replate plated barrels. We also provide ride in, ride out services. Just bring your bike to us, we will remove the engine, do the work required, refit the engine and setup on the Dyno. Call us on the number at the bottom of this page for a competitive quote.

Honda VFR800 837cc Big Bore Kit

74mm Bore, 12.5:1 Compression Ratio

4mm Overbore Size

Barrels require bore and hone

more stuff also.

Description Product Name Manufacturer Part No. Price

Power Commander 1998-1999, USB... VFR800 FiW-FiY Dynojet 101-411 £214.20

Power Commander 2000-2001, USB ... VFR800 Fi1 Dynojet 106-411 £214.20

Power Commander, 2002-2005, 2 x... VFR800 VTEC Dynojet 111-411 £214.20

Power Commander, 2006, USB model, Fuel A... VFR800 VTEC Dynojet 126-411 £214.20

Zero Gravity Double Bubble Scre... VFR800 1998-2001 Double Bubble Screen Zero Gravity 16-453 £55.00

Zero Gravity Double Bubble Scre... VFR800F1 Interceptor 2002 Double Screen Zero Gravity 16-454 £55.00

Zero Gravity Stock Replacement ... VFR800 1998-2001 Stock Replacement Zero Gravity 20-453 £55.00

Zero Gravity Stock Replacement ... VFR800F1 Interceptor 2002 Stock Zero Gravity 20-454 £55.00

Zero Gravity Sport Touring Scre... VFR800 1998-2001 Sport Touring Zero Gravity 23-453 £55.00

Zero Gravity Sport Touring Scre... VFR800F1 Interceptor 2002 Sport Zero Gravity 23-454 £55.00

New Techlusion fuel injection m... TFI Fuel Injection Manager Techlusion All £149.95

Honda VFR800 837cc Big Bore Kit... VFR800 98-01 837cc Big Bore Kit JE Pistons H0839 £400.00

K and N Filter. Improves filtra... VFR800 Air Filter K and N HA-8098 £30.01

DNA air filter for improved per... VFR800 FiW-FiY (98-99) Air filter DNA HD8S04 £34.60

DNA air filter for improved per... VFR800 Fi1 (00-01) Air filter DNA HD8S04 £34.60

DNA air filter for improved per... VFR800 VTEC (02-05) Air filter DNA HD8S04 £34.60

Welcome to the world of Pipercr... Honda VFR800FiW-1 98-01 Pipercross MPX033 £49.50

Welcome to the world of Pipercr... Honda VFR800 VTtec 02> Pipercross MPX060 £49.50

Displaying 1 to 18 (of 18 products) Result Pages: 1

Too bad there all the way in Europe. <_< I don't even want to imagine the shipping charges to send a 150 lbs engine overseas. At £400, it's sounds like a bargain, especially since you can just ride on in.

Nailer45from across the pond though..

http://www.tts-performance.com/catalog/pro...products_id=472

VFR800 98-01 837cc Big Bore Kit

£400.00

H0839

JE Pistons supply the highest quality forged pistons on the market. Most of our kits come complete with Pistons, Pins, Circlips and Rings. Standard bore piston kits do not come with piston rings. At TTS we can bore your cylinders, fit sleeves if required, bore and replate plated barrels. We also provide ride in, ride out services. Just bring your bike to us, we will remove the engine, do the work required, refit the engine and setup on the Dyno. Call us on the number at the bottom of this page for a competitive quote.

Honda VFR800 837cc Big Bore Kit

74mm Bore, 12.5:1 Compression Ratio

4mm Overbore Size

Barrels require bore and hone

man oh man would I love it if my bike had an honest 900 cc's. Not just calling an 830 cc bike a 900.

This kit offers a 7.1 % increase in displacement for

400.00 GBP = 799.610 USD

United Kingdom Pounds United States Dollars

That seems like a pretty expensive proposition. And I doubt that includes the labor.

Who among us couldn't stand to lose 7% of our body weight? I know I could.

Less money spent on food and an increase in performance with no possibility of change in the bike's reliability.

But........ if they could get me to 900 cc's for less than the cost of another bike, that would be a different story.

We need a US based company to use this kit and do the work here. Man that would be awesome 837cc of VFR power.. someone here on this site had it done and the difference If I remember correctly was the Horsepower was increased to 117-120hp.

That would be fun playing with the newer 600 gixxers and CBR600RR guys.. Just wonder what the top end speed would be brought up to..

Secretly, in the back of my mind,I hope that after a year or so of running fine,my bike will develop some nasty oil burning habit or something, which'll force me to get this kit fitted! The thing is with these sort of kits is that often the increase is due to more than just an increase in CC's, it's because you've got forged pistons, perhaps higher compression ratios and also better designed profiles etc. I don't know what sort of scope there is for the vfr, but on my last bike, a TRX850 twin, the kit takes it from 80hp to about 95hp, despite only increasing the displacement by about 30cc.

And, no, the £400 is not including labour...

120hp is available with a big bore kit (Lorenzo's right about the result being more than the sum of the parts) but that's with a full exhaust system - so add another few hundred to the total. Plus a full gasket set... it adds up.

Around $3k for parts, machining, assembly is what I recall Dynamo Humm (Quebec) charging when they were doing big bore VFRs.

I thought the 750 big bored to 840, and the 5th gen 781 went out to 870?

We wont need this anyway, not with a Toro1 supercharger kit smile.gif

Nailer45... Just wonder what the top end speed would be brought up to..

I can understand wanting quicker acceleration, but the problem for you is not enough Top End Speed?

Motor_Refman oh man would I love it if my bike had an honest 900 cc's. Not just calling an 830 cc bike a 900.

This kit offers a 7.1 % increase in displacement for

400.00 GBP = 799.610 USD

United Kingdom Pounds United States Dollars

That seems like a pretty expensive proposition. And I doubt that includes the labor.

Who among us couldn't stand to lose 7% of our body weight? I know I could.

Less money spent on food and an increase in performance with no possibility of change in the bike's reliability.

But........ if they could get me to 900 cc's for less than the cost of another bike, that would be a different story.

Haha.. that analogy does not work. The sum total of weight on a bike is not the riders weight, but the rider and bike together. Figure the bike at 557lbs, and the rider at 180lbs for a total of 737lbs. Lose 7% of that puts the total at 685lbs. Since the bikes weight does not change the rider would have to lose 52lbs, or 29%. I know I am overweight, but I would look crazy if I lost 29% of my body weight.

Also, displacement to horsepower is not alway linear. From previous reports one should expect a 20% increase in horsepower from this 7% increase in displacement. I think the price is a ok, but only if you were going to crack open the motor anyway.

I want this baaaaad.

It would make my vfr relevant again

AB-OzI thought the 750 big bored to 840, and the 5th gen 781 went out to 870?

Correctamundo. Typo in the first post (which appears to be a cut and paste from a website).

We wont need this anyway, not with a Toro1 supercharger kit smile.gif

:thumbsup:

VifferPilot

Nailer45... Just wonder what the top end speed would be brought up to..

I can understand wanting quicker acceleration, but the problem for you is not enough Top End Speed?

NO dont need more speed , I was just curious about it..My VFR is fast enough for me..I myself if I had the $$$ would put the kit in a salvage VFR and use it on the track...

The Phantom

AB-OzI thought the 750 big bored to 840, and the 5th gen 781 went out to 870?

Correctamundo. Typo in the first post (which appears to be a cut and paste from a website).

We wont need this anyway, not with a Toro1 supercharger kit smile.gif

:thumbsup:

The website listed the 837cc kit for a VFR800 98-01 model..click on the link in the first post.. LOL

Nailer45The website listed the 837cc kit for a VFR800 98-01 model..click on the link in the first post.. LOL

Actually (I thought it looked like a lift from the web page) they might just make an 837 kit for the 800 - the pistons might be half the usual big bore diameter increase - can't recall the specs offhand but as an example +.030 might give 870cc but +.015 might give 837cc?. Someone more curious than me could do the exact math based on the known OEM VFR800 piston size...

Over the years, the various postings on the big bore bikes that emerged as they were built have invariably had links to or images of dyno charts with that 120hp mark showing clear as day - at the wheel.

Here's a previous topic that describes in a bit of detail the ins and outs of the big bore option. Has a pic of a classic 4th Gen too.

AB-OzWe wont need this anyway, not with a Toro1 supercharger kit smile.gif

Unless of course, you get the big bore and the supercharger!

837cc pistons for the VFR750F:

vfrproject.zuigers.01.JPG

Cilinders honed:

vfrproject.cilinders.01.JPG

Yummy. Nice to see you back vfroem.

Is it show and tell? :P

P4180055x.jpg

Interesting carbon pattern. Can't remember hom many miles this was--had to pull the front head to get it fixed (by TTS) after it had been cracked (by TTS).

Ciao,

$3,000 is a lot of dough for another 20 or so ponies. :rolleyes:

I went for upping it about 40 with a different Honda, and kept the VFR as is.

Going on 58,000 and still burns no oil, runs great. :thumbsup:

LOL, I've seen Lee's machine. Clean, runs nice, no smoke. Truth, all of it.

VFR4Lee$3,000 is a lot of dough for another 20 or so ponies

Obviously, a big bore kit with fancy pistons is never going to be cheap, but the real problem you've got isn't the cost of doing the job, it's all about the exchange rate I'd guess. Take a look at ebay.co.uk and you'd say everything here was way overpriced, I look at ebay.com and think it's full of bargains (until I have to pay the import duty).

£1500 ($3000) is the cost of a full akrapovic ti system for a modern sports bike, and it's about what you'd expect to pay for a '94 cbr600 or something similar, '98 vfr800's are fetching about £2300 or so, just to give it a bit of context. It's not cheap, but it's not a fortune either.

Hi all.

I fitted an 837cc JE piston kit to my '97 RC36 based track bike.

Luckily, I'm a mechanic so was able to strip and rebuild the motor myself - saving £££.

TTS (UK) supplied the JE piston kit for £440 and rebored the cylinders for £120.

On top of that was the additional cost of approx £50 for gaskets / seals etc.

The head gaskets needed slightly modifying, but no problem. Just enlarging to suit increased bore size

The result... Superb ! An increase in power everywhere. Pulls like a train and makes my standard VFR750 feel gutless.

I havn't had it on a dyno yet, so I can't say how much of an improvement... but I can't imagine any other mod (other than forced induction or nitros) giving a similar BHP gain per £ or $.

My bike hangs onto CBR900's and eats 748's on the track, and has a nice linear power delivery which really drives out of corners.

Induction noise is fab, thanks to RC30 airbox with K&N filter.

JE pistons give an increased compression ratio and narrower squish band, as well as the capacity increase.

I believe that JE's RC30 spec pistons can also be used in the VFR 750. These only have 1 compression ring, but are probably not suitable for road use.

I wish i'd known about these when I built my engine.

I was lead to believe that the JE pistons supplied by TTS where manufactured in the USA. Boring the cylinders should be possible by any decent engine machining specialist.... Maybe a gap in your market ?

With regards to the VFR800..

Some time ago I spoke to a gentleman based here in the UK, who is widely regarded as God of Honda V4 tuning. (RC30's /45's etc.)

He took a non VTEC 800 and built a blueprinted motor, with a capacity of over 900cc using CBR900 Fireblade pistons.

"It went very well" He said... I think that was probably a bit of an understatement !

Cheers, Andy (UK)

Andy GriffInduction noise is fab, thanks to RC30 airbox with K&N filter.

Tell me more about the RC30 airbox, please!

Andy GriffI was lead to believe that the JE pistons supplied by TTS where manufactured in the USA. Boring the cylinders should be possible by any decent engine machining specialist.... Maybe a gap in your market ?

DH eventually developed their own VFR800 big(ger) bore kit, using JE pistons (but this time to DH's spec) and new sleeves, but I don't know how many engines were actually done before they stopped. I think that was the 870cc kit referred to above.

'Blade pistons--I'd heard that before. (Was the tuner Tony Scott?) It wouldn't surprise me if there were other OEM pistons that could be used...Amusingly, the NC30 and NC29 shared pistons, and those were two completely different 400cc engine designs.

The aforementioned "Torocharger" for the VFR800Fi (in development and chronicled on this site) does seem like it would give you all you could possibly need in terms of VFR horsepower, but I can't help wondering what supercharging combined with a substantial displacement increase might be like... +1.gif

Ciao,

The TTS/JE pistons for the RC30 are three ring, not two ring like the originals. That's one of the main reasons I got them, instead of the two ring. That, and my RC30 was already at the largest Honda oversize (70.4mm). I bought a set of the 72mm pistons so my displacement will be the same as the VFR800 (781cc).

I already built my '86 VFR750 with the 74mm kit, so it's 837cc. I thought about boring the RC30 out to 74mm, but this will give me one more size in case something happens to the engine at 72mm. The two ring pistons don't add a lot or power, but they DO require a re-ring more frequently. The RC30 manual even suggests replacing the rings every race weekend. I'm going to do whatever I can to add longevity to the engine, so the three ring makes more sense, unless you're actually racing it. I rebuilt the engine less than 6000 miles ago, and there was enough crankcase pressure to force oil up into the airbox through the breather. So, it was time for a re-ring, but I went for the displacement increase along with the three ring pistons instead.

Hopefully, I'll get the engine put back together by this spring. I recently got the pistons back from Swain Technology, with the thermal barrier coating on the dome and the PC-9 on the skirts. I wish I would have though about this for the VFR pistons, but I built that engine several years ago. I'm going to send the cases to Millenium for boring. I haven't decided on what I'm going to do with the crank or heads yet.

Hi Andy,

Did you modify the RC30 airbox ?

On the dyno my results were much better after making extra holes in the airbox. (I also have a 837cc)

The result with the (bigger) RC36 airbox was better than with the RC30.

But at the moment I have the Durbahn -www.durbahn.de- carbon (RC30) which is even more bigger than the RC36.

Did you already try different cabs ?

Let me know your results on the dyno !

Andy GriffHi all.

I fitted an 837cc JE piston kit to my '97 RC36 based track bike.

Luckily, I'm a mechanic so was able to strip and rebuild the motor myself - saving £££.

TTS (UK) supplied the JE piston kit for £440 and rebored the cylinders for £120.

On top of that was the additional cost of approx £50 for gaskets / seals etc.

The head gaskets needed slightly modifying, but no problem. Just enlarging to suit increased bore size

The result... Superb ! An increase in power everywhere. Pulls like a train and makes my standard VFR750 feel gutless.

I havn't had it on a dyno yet, so I can't say how much of an improvement... but I can't imagine any other mod (other than forced induction or nitros) giving a similar BHP gain per £ or $.

My bike hangs onto CBR900's and eats 748's on the track, and has a nice linear power delivery which really drives out of corners.

Induction noise is fab, thanks to RC30 airbox with K&N filter.

JE pistons give an increased compression ratio and narrower squish band, as well as the capacity increase.

I believe that JE's RC30 spec pistons can also be used in the VFR 750. These only have 1 compression ring, but are probably not suitable for road use.

I wish i'd known about these when I built my engine.

I was lead to believe that the JE pistons supplied by TTS where manufactured in the USA. Boring the cylinders should be possible by any decent engine machining specialist.... Maybe a gap in your market ?

With regards to the VFR800..

Some time ago I spoke to a gentleman based here in the UK, who is widely regarded as God of Honda V4 tuning. (RC30's /45's etc.)

He took a non VTEC 800 and built a blueprinted motor, with a capacity of over 900cc using CBR900 Fireblade pistons.

"It went very well" He said... I think that was probably a bit of an understatement !

Cheers, Andy (UK)

carbonairbox.01.JPG