Just wondering if anyone here is running carbs off different bikes. I'm not talking about dropping a grand on a set of flat slides. CV36BS are a decent carb but are getting a bit long in the tooth are there more modern alternatives that have any advantages?
Also anyone in the U.K. with a broken CV36BS going for beer money. I want something I can cut up.
Well, I did just see a post on FB from a guy who runs fuel injection...
:D
Beyond that, I really don't think carbs significantly advanced from the time of the BS series. There is only so much advancement you can put into a mechanical sprayer.
Have a read: http://www.fjmods.co.uk/Carburation.htm (http://www.fjmods.co.uk/Carburation.htm)
The carb spacing for the FJ is 77 - 85 - 77
Currently 3 options that I'm aware of
1) Mikuni RS flatslides
2) Mikuni TMR roller flatslides
3) Keihin FCR roller flatslides
All 3 of the above carbs have accelerator pumps and offer *immediate throttle response* unlike our CV carbs that have a slight delay while you wait for the vacuum to raise the slide and needle. They are offered in larger sizes (38/40mm) that will flow more air than our 36mm carbs. These carbs, along with the correct cams can give you 20-30+ more rwhp and....did I mention *immediate throttle response*.....I was startled when I rode a FJ with flatslides.
I know both Franks use the Keihin FCR's on their 1350's, (Brutus and Wizard)
The flatslides are racing carbs, the drawback is they do not compensate for air density (altitude) like our CV carbs.
Although Frank has reported that his Wizard has no trouble at sea level and at altitude.
Cheers
Coincidentally I just got back from a ride with Ian between Washoe valley and Reno on my fj1100 with rs-38 flatslides . I've almost got the jetting perfect now. Ian took off on his zzr1200 that would eat my lunch in the past on a section of road with an uphill grade at 5300 ft altitude and this time it was hanging pretty well with his . It hit 150 mph indicated and it still had power to accelerate. The midrange is also excellent and when I finish getting the jetting right I think my idle to eigth throttle will be strong. My flatslides were well worth a thousand bucks to me.
Quote from: T Legg on April 10, 2020, 08:16:37 PM
Coincidentally I just got back from a ride with Ian between Washoe valley and Reno on my fj1100 with rs-38 flatslides . I've almost got the jetting perfect now. Ian took off on his zzr1200 that would eat my lunch in the past on a section of road with an uphill grade at 5300 ft altitude and this time it was hanging pretty well with his . It hit 150 mph indicated and it still had power to accelerate. The midrange is also excellent and when I finish getting the jetting right I think my idle to eigth throttle will be strong. My flatslides were well worth a thousand bucks to me.
Just curious, do you find the stronger return springs hard to hold for longer distances. What mods have you done to the engine as I would've thought the carby's alone wouldn't be enough to keep with a ZZR
The throttle springs are stiff but they don't bother me on long trips. I do use a cramp buster to relax my grip .the motion pro throttle assembly requires a lot of rotation to reach full throttle . My bike was set up in the late eighty's by the original owner.it had rs- 36 carbs four in to one exhaust and pod filters . The suspension was also set up by Lindemann enterprises with a Penske shock and the antidive units removed. I've not had the heads removed I assume it's stock inside. I can see that someone match ported the heads to the intakes but I can't see any other porting from the outside. The cam shafts have slotted gears but I don't know if they are stock or not,they look the same as the cams on my other two fj's. With the rs - 36 carbs on it the highest speed I had hit was 146 mph at 4900 ft elevation on level ground and it was almost out of poop by then although I did have saddlebags on at the time. My son's zzr would pull away from it pretty well on long straight aways. With rs-38 carbs on yesterday's run at 5300 ft elevation going up a decent incline it hit 150 mph and was still accelerating. My son on his zzr ahead of me hit 162 mph and was only easing away from me.all these speeds were speedometer readings the actual speeds could be ten to fifteen percent off.In twisty road riding I don't feel any disadvantage to the zzr. My FJ 1100 with the flatslides is much faster than my fj1100 or my fj1200 that both have stock carbs four into one exhaust and pod filters.
Quote from: JPaganel on April 10, 2020, 05:54:48 PM
Well, I did just see a post on FB from a guy who runs fuel injection...
:D
Do you have a link?
Quote from: Little Pink Steve on April 11, 2020, 05:37:45 PM
Quote from: JPaganel on April 10, 2020, 05:54:48 PM
Well, I did just see a post on FB from a guy who runs fuel injection...
:D
Do you have a link?
https://www.facebook.com/groups/1440193869604433/permalink/2370634806560330/ (https://www.facebook.com/groups/1440193869604433/permalink/2370634806560330/)
Quote from: T Legg on April 11, 2020, 10:15:58 AM
The throttle springs are stiff but they don't bother me on long trips. I do use a cramp buster to relax my grip .the motion pro throttle assembly requires a lot of rotation to reach full throttle . My bike was set up in the late eighty's by the original owner.it had rs- 36 carbs four in to one exhaust and pod filters . The suspension was also set up by Lindemann enterprises with a Penske shock and the antidive units removed. I've not had the heads removed I assume it's stock inside. I can see that someone match ported the heads to the intakes but I can't see any other porting from the outside. The cam shafts have slotted gears but I don't know if they are stock or not,they look the same as the cams on my other two fj's. With the rs - 36 carbs on it the highest speed I had hit was 146 mph at 4900 ft elevation on level ground and it was almost out of poop by then although I did have saddlebags on at the time. My son's zzr would pull away from it pretty well on long straight aways. With rs-38 carbs on yesterday's run at 5300 ft elevation going up a decent incline it hit 150 mph and was still accelerating. My son on his zzr ahead of me hit 162 mph and was only easing away from me.all these speeds were speedometer readings the actual speeds could be ten to fifteen percent off.In twisty road riding I don't feel any disadvantage to the zzr. My FJ 1100 with the flatslides is much faster than my fj1100 or my fj1200 that both have stock carbs four into one exhaust and pod filters.
Thankyou sounds like a neat FJ you have there
Thanks for the replies guys.
I'll rephrase the question. Are there any OEM carbs from other bikes that would work well on an FJ1200? Happy to re-engineer them to fit, only mods to the bike are 4-1 pipe and some head work (possibly filters or airbox mods). I don't fancy dropping £3k into it.
Quote from: JPaganel on April 11, 2020, 07:59:13 PM
Quote from: Little Pink Steve on April 11, 2020, 05:37:45 PM
Quote from: JPaganel on April 10, 2020, 05:54:48 PM
Well, I did just see a post on FB from a guy who runs fuel injection...
:D
Do you have a link?
https://www.facebook.com/groups/1440193869604433/permalink/2370634806560330/ (https://www.facebook.com/groups/1440193869604433/permalink/2370634806560330/)
Seems like a decent deal for someone
^^ Wrong spacing, you want 77-85-77
Quote from: Pat Conlon on April 12, 2020, 10:05:59 AM
^^ Wrong spacing, you want 77-85-77
I wonder how he had them mounted on his FJ dwarf car? Interesting!
Good catch
https://www.facebook.com/groups/1343924852335564/ (https://www.facebook.com/groups/1343924852335564/)
I believe the spacing can be changed on the brackets.
"Check your carb spacing as per the picture and if not 77-93-77 as supplied here but only requiring a 77-85-77 spacing adjustment this can be either done by yourself or we can do it by selecting the re-spacing labour option for $88 in the RS carbs accessories page"
https://www.mikunioz.com/shop/rs40-d1-k-mikuni-rs-40mm-carb-kit/?v=7516fd43adaa (https://www.mikunioz.com/shop/rs40-d1-k-mikuni-rs-40mm-carb-kit/?v=7516fd43adaa)
*** Update ***
The spacing is correct, the seller used generic information for his listing. Here is a picture of them next to a set of stock FJ carbs.
Good to go! :good:
The carbs from a 1st generation FZ1 have spacing that's identical to the FJ.
The FZ1 carbs are very similar to the FJ carbs. Both are Mikuni, the FZ carb is a modern version of the FJ.
Not sure on the performance difference. Ivan makes a carb kit for the FZ that really improves throttle response.
Quote from: FJ_Hooligan on April 13, 2020, 02:13:39 PM
The carbs from a 1st generation FZ1 have spacing that's identical to the FJ......
Are you sure amigo? 77-85-77
I thought the FZ1 engine was a modified version of the YZF-R1 so the cylinder spacing is different.
Pat,
Prior to that post I set them on top of each other and the intakes lined up perfectly. Even with the cam chain on the end, the intake spacing of cylinders appears to be the same.
I'd take a picture but it's such a pain to post pics on this site.
Check over on FB
I'm almost offended that you question a statement about carbs from me. :-)
(http://fjowners.com/gallery/11/49_14_04_20_9_00_24.jpeg)
David....yea, what was I thinking? I pulled your photo over from FB.
I looked all over the web for the FZ1 carb spacing
The Yoshurmia web site has the most complete listing for aftermarket carb fitments and strangely enough they have no carb listings for the early FZ1's or Fazers as they are known overseas.
Don't I remember (years ago) you saying the FZ1's carbs were a PIA to work on?
Wrangling the spacers and sync springs is a PITA but they aren't terriblly bad.
The Ivan carb kit for the FZ1 carbs is a significant improvement over stock. My son's Bumblebee FZ has one and it is noticeably stronger on acceleration than my stock FZ
Years ago I postulated that the spacing was similar but never confirmed it until now
So if the carb spacing is the same, the exhaust header should also fit?
Is the firing order on the FZ1 the same 1243 as our FJ's?
Quote from: FJ_Hooligan on April 14, 2020, 08:49:23 PM
Pat,
I'm almost offended that you question a statement about carbs from me. :-)
Haha David....
.... don't feel special. :biggrin:
Pat,
The exhaust spacing doesn't necessarily mimic the intake spacing. The intake spacing was probably kept the same to fit an existing set of carbs that Mikuni already had in production, saving the cost of reworking a new spacing. Since the FJ has a center cam chain and the FZ1 has the chain on the right side of the motor, I would assume the intake runners are different lengths because the cylinder spacing is definitely tighter than the FJ.
And basically, they can channel the exhaust spacing to whatever they wanted/needed regardless of intake measurements.
Funny Noel. :-)
So if the carb spacing is the same from carb'd FZ1 to FJ, does that mean the fuel injected ones have similar spacing on the throttle bodies?
First dimension I could find is that the FJR1300 throttle bodies are 78-88-78, which seems like the sort of difference you could make up in the intake boots, maybe with a heat gun or maybe just pulling the two inner ones 3mm closer together (less than 1/16" each.)
Bill, yes, the FJR throttle bodies are what Randy used on his FI system he developed for the FJ.
Randy had offset adaptors made to mate the FJR throttle bodies up to the 77-85-77 spacing of the FJ's intake ports.
However, like you asked...If the FZ1 throttle bodies have the same pitch as the early FZ1 carbs, we would not need offset adaptors.....Interesting.
I bet a jelly donut David knows the answer.
The classics come back.....from 9 years ago....
http://www.fjowners.com/index.php?topic=3381.0 (http://www.fjowners.com/index.php?topic=3381.0)
I had to laugh....even back then someone had the balls to question the carb guru....
I wonder if Dan ever got his $5?
I don't even remember that Pat. I guess I did do my homework back then but for....zzzzzzzzzzzzzz...got. Sorry, had to take a short nap in there,
Also, I know nothing about the 2nd gen FI FZ1. All of mine are 1st gen carbs.
I think I bought that set of FZ carbs that Ed was selling back then
Dan had a lot of faith in me. :-)
David, well now, as of yesterday, we can put your theory to bed. :good:
I noticed the lip on the FZ1 carbs (manifold side) looks to be shorter than on the FJ carbs, do you think those FZ1 carbs will snap into the FJ's intake boots correctly?
On street bikes I'm a fan of CV carbs. However with my 1380cc engine (thank you RPM) using heavily rejetted CV36 FJ carbs, I notice at ~8.2k to 9.0k rpm the arm stretching acceleration tapers off. The 36mm carbs run out of air flow. Even still, this bike has some serious kookaloo....
So using the logic of simple math from a 1200cc stock FJ engine I've increased the displacement 13% to 1380cc.
So at larger displacement comes a proportional increase in air velocity feeding those 83mm dia. Ross pistons.
Therefore if my 1200 cc stock engine is served by 36mm dia. Mikuni CV carbs, why not try some Mikuni CV carbs with 13% more area? What size would I need?
The area of 36mm is 101.7cm x 1.13 = 115cm
The area of a 38mm carb is 113cm...close enough.
Now where would I find a rack of 38mm Mikuni CV carburetors?
The 1990-94 GSXR 750 European version used what is known as the Mikuni BST38SS carbs (aka Slingshot carbs)
(https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcSDLJBoZnHdSVKcFSs9NbCMUQOjqgtNGNeiqXHO4XD9QtsOHO1R&usqp=CAU)
(https://i0.wp.com/oldskoolsuzuki.info/wp-content/uploads/2015/07/bst38ss-1.jpg?fit=189%2C287)
The problem is the GSXR carb spacing of 77-93-77 so these 38mm carbs must be modified to fit the FJ 77-85-77 spacing.
Several years ago I found a set for sale in England (the USA versions were only 36mm)
I sent them up to RPM for Randy to take a look see and get modified, as a low priority project.
Until today, I've totally forgotten about them. Perhaps Robert can track them down. If times get slow, he can learn all about a completely different model of Mikuni Carb.
https://www.partzilla.com/catalog/suzuki/motorcycle/1992/gsx-r750n/carburetor-other-than-califorina (https://www.partzilla.com/catalog/suzuki/motorcycle/1992/gsx-r750n/carburetor-other-than-califorina)
http://oldskoolsuzuki.info/archives/531 (http://oldskoolsuzuki.info/archives/531)
http://didier.clergue.free.fr/gsxr/docspdf/mikuni_bst_understanding_carburetors.pdf (http://didier.clergue.free.fr/gsxr/docspdf/mikuni_bst_understanding_carburetors.pdf)
I stumbled on this fuel injection setup -
Steve, those look cool but no way would they fit between the frame rails on our FJ's.
The XJR uses a backbone frame so there is plenty of room at the sides of the FI throttle bodies...not so with FJ's perimeter frame rails....how they taper in towards the seat.
Yes, of course the XJR throttle bodies matches the FJ cylinder spacing (same engine) but the throttle body assembly has a left side protuberance for the throttle position sensor...thus does not fit between the FJ frame rails.
That's why Randy went with the narrower FJR throttle bodies....that, and the fact that they are plentiful on FleaBay.
Cheers
Quote from: Pat Conlon on April 15, 2020, 04:37:53 PM
Steve, those look cool but no way would they fit between the frame rails on our FJ's.
That was a build for a midget race car. If you think the FI wont fit, check out the mechanical fuel pump mounted to the left side of the valve cover driven from the intake cam...
I don't know much more about the set-up except where the intake manifolds came from.
Randy - RPM
Quote from: Pat Conlon on April 15, 2020, 03:43:42 PM
Until today, I've totally forgotten about them. Perhaps Robert can track them down. If times get slow, he can learn all about a completely different model of Mikuni Carb.
Don't worry, I know exactly where they are. Unfortunately, we have a NY bike to finish first...
Randy - RPM
Quote from: FJ1200W on April 15, 2020, 04:05:04 PM
I stumbled on this fuel injection setup -
Randy - is that a mechanical FI setup?! Very cool!
Quote from: racerrad8 on April 15, 2020, 04:41:54 PM
Quote from: Pat Conlon on April 15, 2020, 03:43:42 PM
Until today, I've totally forgotten about them. Perhaps Robert can track them down. If times get slow, he can learn all about a completely different model of Mikuni Carb.
Don't worry, I know exactly where they are. Unfortunately, we have a NY bike to finish first...
Randy - RPM
No worries, I'm in no hurry at all.....
Quote from: Pat Conlon on April 15, 2020, 04:37:53 PM
Steve, those look cool but no way would they fit between the frame rails on our FJ's.
The XJR uses a backbone frame so there is plenty of room at the sides of the FI throttle bodies...not so with FJ's perimeter frame rails....how they taper in towards the seat.
Yes, of course the XJR throttle bodies matches the FJ cylinder spacing (same engine) but the throttle body assembly has a left side protuberance for the throttle position sensor...thus does not fit between the FJ frame rails.
That's why Randy went with the narrower FJR throttle bodies....that, and the fact that they are plentiful on FleaBay.
Cheers
Agreed on all counts.
What was ever decided on FZ1 throttle bodies? It sounded like the 1st gen carbs might work with custom intakes.
All dreamland too me, I'm on a cut throat budget.
Just fitted a set of 2001 FZ1 carburettors to my 3CV, I got these for a good price so I had nothing to loose. Background to my bike, wiseco 1219 kit ( done about 130K kms), Porting , standard valves, 36Y inlets matched to ports, Web cams - street, 4-1 Marving.
Anyway before fitting I following the Ivan's modifications, can't buy the kit in Oz so a bit of guess work was required. I drilled the slides for quicker response, set float levels from 12 to 14mm heights, drilled two idle jet ports. The choke cable is standard but the bracket on the carbies was bent to clear the heat plate and the cable required a minor mod the screw down to the bracket
Fitting the FJ, the standard throttle cables fit direct, Carbies fit direct to intakes, even though the intake throats are 58mm vs 55 Standard the RPM dual socks fit with a bit of stretch.
The Carbies are about 15mm shorter so might be a problem if using a standard air filter box.
The Run, was done with an LM2 AFR meter fitted to a bung on the exhaust. Idle at 3.5 turns out was spot on at 14.7 hot. The bike ran around 13.2 to 13.5 cruising and 12.5 hard acceleration. So minor jetting required ( I fitted 128 mains from 132 standard, so I might fit 125) and pilot will go from 42.5 standard to 40.
The feel with current settings, from 50kph on top gear pulls clean, engine is smother, although seat of the pants feels stronger especially mid and top I won't make any claims until a dyno is done after re-jetting.
WOW mate, you don't mess around!
When are you planning the Dyno?
Any chance you and the missus will be over for the rally in Bermie next year?
Troyskie
Quote from: Troyskie on December 19, 2021, 03:46:49 PM
WOW mate, you don't mess around!
When are you planning the Dyno?
Any chance you and the missus will be over for the rally in Bermie next year?
Troyskie
Troyskie, we have bookings for the rally but all depends on the Little bugs behaving themselves.
As for the Dyno, I hope to get the jets soon and setup the carbies. At present (old carbs) I had 131RWhp, I don't expect huge leaps but it feels better than before. I should have the dyno run soon. I'll post the results here (if they are good), if not I'll go in the naughty corner, hang my head in shame and start riding a Virago.
Update on FZ1 carbies.
The jetting is complete and the AFR through out the range is the best I've seen. Cruising, idle AFR is around 14.5, under acceleration around 13. The topend at about 7500rpm went lean at 15, 16 so eventually a 135 mains was fitted, the needle was dropped one notch (to lean lower end which was 13.4 cruising), all else remains. End of January I have a dyno booked. I hope to avoid the naughty corner (if power drops) the feeling is the opposite will happen. Honestly I expect a slight increase but the clean power without rich spots ( I had with std carb's).
Economy was better than before, cruising (varying speeds - not totally slow) I got 345kms for 18ltrs (exactly), I'd guess that under power this would change with the bigger jets.
Disclaimer - this setup suits my bike but don't expect the same for other setups. Was it worth it - hell ye, I now have as new carbies, whereas my old carb's were showing signs of requiring parts etc
Dyno (by Dynotime in WA) results were impressive, top end 135RWHP (previous 131) but the most impressive was the way the power went up. The dyno graphs were a mixed bag because when the first power run was done it recorded 135 but after the poor clutch started to slip. I have a Barnett clutch with heavier than "severe heavy springs" (had them made through a company called Boynes in WA). I checked the plates and no damage detected so it only has slip when engine is not up to temperature.
At 6000rpm it was slightly rich 12 AFR so the curve dipped a bit and the top 8,000rpm up showed 14 AFR so I'll drop the needle a bit and raise the main jet size to 137.5 and then it should be good.
Fuel economy is excellent as long as full power is not used often (better than std- normal riding).
All in all this proved to be a winner for me, the only issue is the clutch but that should be ok as long as I don't power until running temp. I tried the twin pressure plate Yamaha version and I found it very heavy for my older muscles (or lack of). Maybe someone out there has a suggestion on making the clutch stronger without an ape pressing the lever for me.
Quote from: Bozo on January 28, 2022, 10:16:38 PM
I tried the twin pressure plate Yamaha version and I found it very heavy for my older muscles (or lack of). Maybe someone out there has a suggestion on making the clutch stronger without an ape pressing the lever for me.
What master are you using for the clutch? Many that doubled up the OEM spring also went with a 14mm master and found the lever pull was closer to normal.
Quote from: FJmonkey on January 28, 2022, 10:25:56 PM
Quote from: Bozo on January 28, 2022, 10:16:38 PM
I tried the twin pressure plate Yamaha version and I found it very heavy for my older muscles (or lack of). Maybe someone out there has a suggestion on making the clutch stronger without an ape pressing the lever for me.
What master are you using for the clutch? Many that doubled up the OEM spring also went with a 14mm master and found the lever pull was closer to normal.
I'll look into this, I have a clutch cylinder used on the ZZr1100 Kawasaki, I believe these are used on a lot of other models but not sure of the size. I have a similar clutch setup on my Standard FJ with std clutch cylinder and it does feel heavier to pull. Thankyou for your suggestion.
What is the standard FJ master size?
Quote from: Bozo on January 28, 2022, 10:16:38 PM
Maybe someone out there has a suggestion on making the clutch stronger without an ape pressing the lever for me.
Bozo, unfortunately nothing's for free in physics, if you want an easier pull for a given pressure? a smaller diameter m/c will do it but it comes at the cost of a longer throw, that is, the take up point is now nearer the bars and the fully engaged position is further out. It is the hydraulic equivalent of using a longer bar to exert more rotational force, it makes it easier but the end of the bar has to move further. Many owners are not bothered by this and some are.
The nearest we get to cheating physics is an overcentre spring (like the standard spring or one of those clickers you had as a kid ) as opposed to coil springs which load up in a linear fashion.
Some years back I was in the early stages of fitting a small servo unit (brake booster) to an FJ clutch for an arthritis riddled owner to ease the clutch pull but unfortunately he died before I got too far into it. I've had occasion over the last year or so to revive my interest in the project for personal reasons. I had also considered using a "brake bomb" but in the interest of simplicity and cost, if I was doing it I would proceed with the servo. There are plenty of small cars from which one could be sourced from the wreckers for not much money. The plan was to mount it where the air box had been.
Noel
Quote from: FJmonkey on January 28, 2022, 10:25:56 PM
Quote from: Bozo on January 28, 2022, 10:16:38 PM
I tried the twin pressure plate Yamaha version and I found it very heavy for my older muscles (or lack of). Maybe someone out there has a suggestion on making the clutch stronger without an ape pressing the lever for me.
What master are you using for the clutch? Many that doubled up the OEM spring also went with a 14mm master and found the lever pull was closer to normal.
My ZZR1100 Clutch master is a 14mm, as Ribbert stated the take-up is closer to the handlebar then the FJ master. Even with the Barnett springs it has a lighter pull so if the slip becomes an issue (I'll only run hard when hot) I'll have to revert to using two diaphragm plates. In case you are interested I'm using Penrite 5-40W MC oil.
Quote from: ribbert on January 29, 2022, 06:09:19 AM
Quote from: Bozo on January 28, 2022, 10:16:38 PM
Maybe someone out there has a suggestion on making the clutch stronger without an ape pressing the lever for me.
Bozo, unfortunately nothing's for free in physics, if you want an easier pull for a given pressure? a smaller diameter m/c will do it but it comes at the cost of a longer throw, that is, the take up point is now nearer the bars and the fully engaged position is further out. It is the hydraulic equivalent of using a longer bar to exert more rotational force, it makes it easier but the end of the bar has to move further. Many owners are not bothered by this and some are.
The nearest we get to cheating physics is an overcentre spring (like the standard spring or one of those clickers you had as a kid ) as opposed to coil springs which load up in a linear fashion.
Some years back I was in the early stages of fitting a small servo unit (brake booster) to an FJ clutch for an arthritis riddled owner to ease the clutch pull but unfortunately he died before I got too far into it. I've had occasion over the last year or so to revive my interest in the project for personal reasons. I had also considered using a "brake bomb" but in the interest of simplicity and cost, if I was doing it I would proceed with the servo. There are plenty of small cars from which one could be sourced from the wreckers for not much money. The plan was to mount it where the air box had been.
Noel
Very interesting, let us know how you go. Maybe by then I'll need it.
I have a 1380cc FJ with the Barnett 82lb (green) springs and a FJR master.
No slip and the clutch pull is tolerable.
Quote from: Pat Conlon on January 30, 2022, 08:06:31 AM
I have a 1380cc FJ with the Barnett 82lb (green) springs and a FJR master.
No slip and the clutch pull is tolerable.
Pat, very interesting, I think the FJR is a Nissan Master, my springs are a bit stronger than the green springs (specially made).
I checked the clutch plates and both are in good condition and thickness, so the slip only started when the extra power came into play. Don't forget my slip is only when engine is not to temperature, once in temp it does not slip.
My Standard FJ1200 "Limo" has an extremely powerful totally Std (pods only) motor, it also started to slip (after 110K) when warm but when hot it was ok - it now has a Barnett plate with std springs and even when not at temp it grips. Note I rarely if ever drag a bike not at temp.
On my "evil FJ" with the 14mm Nissan master it is easier (less pull strength) to use but it "grabs" mid way travel. Not a problem as I use this bike for weekend travel and the standard for work (37km one way of work traffic).
I'd love to try the 1380 one day, it must be a torque monster.
Quote from: Bozo on January 30, 2022, 05:08:09 PM
.... totally Std (pods only) motor, it also started to slip (after 110K) when warm but when hot it was ok - it now has a Barnett plate with std springs and even when not at temp it grips.
Bozo, if your standard clutch lasted the first 110k, which is a good innings, why not just replace it and get another 110k,
and, you retain the easy action. Also, a set of friction plates is a lot cheaper than a Barnett conversion and a lot nicer to use.
Not wishing to start a discussion on what does and doesn't slip and under what conditions and on what bikes, but the Penrite oil you're using is full synth, and any way you cut it, synth is slipperier than mineral.
With a Barnett clutch, people only ever talk about the increased pull at the lever and ways to lighten it. The other, and equally significant issue is the linear loading of a coil spring vs the over centre feature of a diaphragm spring.
If you have more power like Pat, Frank or your own "Evil FJ" a heavy duty clutch is a necessary evil but it seems such a shame to compromise the light controls of a stock FJ when there's no need for it, such as on a standard well tuned engine.
The entire automotive industry adopted over centre clutch springs for obvious reasons in the middle of last century, fitting a Barnett coil spring clutch unless you absolutely need to is a throw back to era, and am I correct in thinking Frank's 165 rear wheel HP is handled with a no more than a doubled up standard clutch spring? I doubt there are too many FJ's making more power than that.
You say your fibres plates are within spec thickness, they always are, that's not how a wet clutch plates wear. In my 13 years on this forum and reading of owners being told to measure the thickness of their plates I can't recall a single occasion when they were under spec.
Your observation that is slips more when the oil is not up to temp is normal.
Bozo, I know you've already chosen your path, but the above advice was more taking the opportunity to inform readers who might be experiencing the same problem that there is more than one way to fix it. It's always good to have choices.
Noel
Quote from: ribbert on January 31, 2022, 08:00:30 AM
...am I correct in thinking Frank's 165 rear wheel HP is handled with a no more than a doubled up standard clutch spring?
Correct. Two stock springs and no slips, even when lifting the front in 5th at WOT. FYI - I run Valvoline VR-1 for it's high zinc content... recommended for higher lift cams. Might slip with a synthetic oil??
Frank
Quote from: ribbert on January 31, 2022, 08:00:30 AM
Quote from: Bozo on January 30, 2022, 05:08:09 PM
.... totally Std (pods only) motor, it also started to slip (after 110K) when warm but when hot it was ok - it now has a Barnett plate with std springs and even when not at temp it grips.
Bozo, if your standard clutch lasted the first 110k, which is a good innings, why not just replace it and get another 110k, and, you retain the easy action. Also, a set of friction plates is a lot cheaper than a Barnett conversion and a lot nicer to use.
Not wishing to start a discussion on what does and doesn't slip and under what conditions and on what bikes, but the Penrite oil you're using is full synth, and any way you cut it, synth is slipperier than mineral.
With a Barnett clutch, people only ever talk about the increased pull at the lever and ways to lighten it. The other, and equally significant issue is the linear loading of a coil spring vs the over centre feature of a diaphragm spring.
If you have more power like Pat, Frank or your own "Evil FJ" a heavy duty clutch is a necessary evil but it seems such a shame to compromise the light controls of a stock FJ when there's no need for it, such as on a standard well tuned engine.
The entire automotive industry adopted over centre clutch springs for obvious reasons in the middle of last century, fitting a Barnett coil spring clutch unless you absolutely need to is a throw back to era, and am I correct in thinking Frank's 165 rear wheel HP is handled with a no more than a doubled up standard clutch spring? I doubt there are too many FJ's making more power than that.
You say your fibres plates are within spec thickness, they always are, that's not how a wet clutch plates wear. In my 13 years on this forum and reading of owners being told to measure the thickness of their plates I can't recall a single occasion when they were under spec.
Your observation that is slips more when the oil is not up to temp is normal.
Bozo, I know you've already chosen your path, but the above advice was more taking the opportunity to inform readers who might be experiencing the same problem that there is more than one way to fix it. It's always good to have choices.
Noel
Noel, always open to advice, you are right I have never had a plate that was considered worn. I did get plates from new that were a bit under spec width though. The reason I mentioned the plates originally was because I was worried that the slip that was noticed during the dyno might've been there longer which would've caused the steel plates to warp. As you mentioned if I'm worried in the future I always have the twin plates I can put in. I believe Pete (KTMdude) also runs twin plates and not slip (he has a bit more power than my evil one).
As for the Barnett clutch on my std bike, I got that from a guy who no longer needed his new plate for a bargain $50 so fitting it was a no brainer.
Quote from: Flynt on January 31, 2022, 10:35:37 AM
Quote from: ribbert on January 31, 2022, 08:00:30 AM
...am I correct in thinking Frank's 165 rear wheel HP is handled with a no more than a doubled up standard clutch spring?
Correct. Two stock springs and no slips, even when lifting the front in 5th at WOT. FYI - I run Valvoline VR-1 for it's high zinc content... recommended for higher lift cams. Might slip with a synthetic oil??
Frank
Hi Frank, the Penrite oil is noted for its zinc content which is why I use it, so no problems there. Ye I lifted the front in 5th using my bloody jack - hahaha