ee
Newbe
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Post by ee on Jul 29, 2019 3:08:35 GMT 1
Hey guys we're pulling together a write up on RD/LC/RZ/TZ Engine History/Differences/evolution over on Two Stroke world www.2strokeworld.net/forum/index.php?topic=732.0Can you guys help with some of your of your LC engine differences expertice? We didn't get the LC here in the states, I realize the LC's used the RD style clutch mechanism still but from what I've heard the LC trans is the same as the RZ? So that's what I'm wondering are the LC transmission, shift drum, clutch and all that the same as the RZ?? And any other engine differences we may have missed. Ed |
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Post by tacky1 on Jul 29, 2019 4:25:13 GMT 1
I think the gearbox are different. The drum and shafts are wider on the RZ. 6th gear was made heavier and wider on the RZ. Maybe some of the gears are interchangeable and maybe the shift forks.
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Post by dusty350 on Jul 29, 2019 7:50:07 GMT 1
Hi The Lc and Pv bottom ends are very similar, but as Tacky rightly said, Pv cases are slightly wider internally. Pv crank is wider than an Lc, as is the shift drum, gears differ, clutch operation is different too. If you were to cross reference parts numbers you will see that Lc and Pv, and earlier aircooled numbers cross over a fair bit. The earlier aircooled bottom ends are very different though, and in some respects more complicated than the later water cooled bikes. Lc and Pv crankcase mount dimensions are the same, hence the ease with which you can fit a Pv engine into an Lc frame, but again, differ hugely to the aircooled bikes. Lc/Pv engines have 2 mounting points, aircooleds have 4. Lots of gearbox differences between Ac and Lc - Ac even has a first gear needle roller bearing that the Lc did away with. Lc barrels wont fit Pv bottom ends and vice versa, but you can fit Lc barrels to an aircooled bottom end !! Dusty  |
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Post by earthman on Jul 29, 2019 8:07:54 GMT 1
We didn't get the LC here in the states Surely that can't be right? I know that the States is a huge place so maybe they just weren't popular/sell in some areas?? There are some American LC owners on this site, did they have to find/import these bikes personally then?? |
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Post by midlifecrisisrd on Jul 29, 2019 11:25:02 GMT 1
We didn't get the LC here in the states Surely that can't be right? I know that the States is a huge place so maybe they just weren't popular/sell in some areas?? There are some American LC owners on this site, did they have to find/import these bikes personally then?? It was never officially imported into the USA as far as I know Hence why they got the rd400 daytona as a stopgap It was imported into Canada though so they have made it over into the states Steve |
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Post by veg on Jul 29, 2019 12:01:40 GMT 1
But they did get the pv/lc2
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Post by midlifecrisisrd on Jul 29, 2019 12:05:31 GMT 1
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Post by tacky1 on Jul 29, 2019 14:24:22 GMT 1
But they did get the pv/lc2 Yep, The YPVS was imported for 2 years, No RGs, No LCs, NO 500s, I think the 350 YPVS was the only water cooled smoker imported, then the 2stroke ban |
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Post by pdxjim on Jul 30, 2019 5:53:39 GMT 1
We didn't get the LC here in the states Surely that can't be right? I know that the States is a huge place so maybe they just weren't popular/sell in some areas?? There are some American LC owners on this site, did they have to find/import these bikes personally then?? We got the RD400 Daytona Special in '79, then nothing til the RZ350/LC2/YPVS came out. My 4U0 LC came over direct from Japan, and quite a few found their way down to the States from Canada. We didn't officially get the TDR250 either, but I've got one of those in me garage too. |
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Post by earthman on Jul 30, 2019 7:46:08 GMT 1
Strange that the LC wasn't commonly available in the States, I wonder why??
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Post by mouse on Jul 30, 2019 8:36:56 GMT 1
Strange that the LC wasn't commonly available in the States, I wonder why?? Emissions me thinks. The YPVS's that were imported had all sorts of carb and exhaust nonsense to clean them up! Mouse |
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Dave B
Drag-strip hero
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Post by Dave B on Jul 30, 2019 9:14:33 GMT 1
I saw an American spec YPVS in a shop in Macclesfield that had labels saying that there were catalysts in the exhaust. I'm fairly sure that that is not likely to work well in a two stroke.
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Post by veg on Jul 30, 2019 9:26:43 GMT 1
I Know that the Californian lc2 had catalysts did other states have them?
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Post by midlifecrisisrd on Jul 30, 2019 10:54:34 GMT 1
No
Just the Californian model as far as I know
Think the rest had the linked push/pull carbs like the 250
Steve
Steve
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ee
Newbe
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Post by ee on Aug 1, 2019 22:56:38 GMT 1
OK guys here's the finished write up!
History and differences between RD250,350,400, 73-80 TZ, LC, and RZ engines
(From the 1970 DS7/R5 to the 1990 reverse cylinder TZ250)
(Note: for ease of reference I refer to 73-80 TZ‘s as “early TZ‘s“)
1962 The RD56 Yamahas first World Grand Prix Champion winner (56x50 rotary valve 250)
1967 The YR1 Yamahas first horizontally split parallel twin (61x61 350 2 transfer piston port)
1970-1972 DS7/R5 start of the 4 transfer port cyl base/case layout that form the basis for the RD and early TZ series
DS7 / TD3 250
R5 / TR3 350
TA250 early 1973 aircooled TD3/TZ hybrid
An interesting point: The some of the "works" TR3 engines from 1972 sported 6 transfer ports, like the 79/80 TZ350
1973-1980 TZ’s used a variant of the “RD” cases but used Piston port monoblock watercooled cylinders
1980 the TZ250 G in a last ditch effort to get ever last hp out of the “RD” based case engines ran an intake so big it became know as the piston eater
1981Yamaha totally redesigned the TZ250 engine. Having reached the limit of intake port size in the G, the H models crankshaft rotation was run backwards to put piston thrust on the cylinder wall opposite the intake allowing further increases in intake port size. The cylinders were now individual but still piston port. Also new was Yamaha's exhaust power valve system
1985 Yamaha again Redesigned the TZ250 engine. 1985-1987. Switching for the first time to case reed induction to create much needed bottom end and widen the powerband. BUT 1985’s reedcages were to small and were quickly enlarged
1988-90 in a last ditch effort to get every last hp out of the parallel twin design Yamaha reversed the cylinders & tilted them forward to 60deg putting the carbs in front & the pipes coming straight out the back under the seat
Because the R5/DS7 was the first Yamaha to use the 4 transfer port cylinder base case layout (2 on each side with a 5th boost port added in the RD series) RD, LC and early TZ cylinders will bolt directly onto the R5/DS7/RD and LC cases.
though you do need to use the correct cylinder stud lengths (Teazer)
BUT the R5/DS7 only had a 5 speed but it is super easy to swap out the gears, shift forks and shift drum for an RD 6 speed setup
TZ cases were a separate casting than RD cases, a very slight variant but still a separate casting, so close though in fact that when TZ racers broke early TZ cases it was super common to replace them with RD cases
TZ cases differ from RD cases in that
the front engine mounts are rubber mounted,
The grooves to locate the TZ crankshaft are cut into the crankshaft inner bearing area instead of the primary side bearing area because the TZ’s used a different crankshaft (that will interchange if you cut the grooves in RD cases) that used Roller bearing outer main bearings
There is an oil passage below the shift drum not "drilled" on TZ cases between the transmission and primary gear sections of the case and the kickstarter boss has a plug in it (Yamaha part number 90338-17016 BH) (Teazer)
The oil drain is in the middle of TZ cases but offset one the RD cases. The center RD crank bearing surfaces normally have a cast in steel insert buy the TZ cases normally don't BH
so TZ cases were more than just RD cases machined for front engine mounts
Early TZ’s had a different transmission, though it can drop right in RD cases it has a VERY tall first gear and much closer gear ratios with a longer mainshaft to allow for the TZ dry clutch
The TZ dry clutch if combined with the TZ transmission or an RD transmission with a special mainshaft will bolt directly into an RD
A TZ dry clutch with a special mainshaft will bolt directly on to an LC
A TZ dry clutch with a special mainshaft and slight modification for gasket sealing to the cases will bolt onto an RZ
Almost all DS7/R5 cases had no grooves in the crankshaft seal area to secure the seal as everything RD and later does but I‘m told some did. And they did not have the mainshaft clutch side bearing retainer behind the clutch
According to the aircooled RD club early RD400 Prototypes had solid mounted engine mounts!
RD400 cases have slight differences in the castings, the earliest had a little less material around the cylinder base gasket area at the rear and more ribbing around the right main bearing and right transmission mainshaft bearing in later cases.
Starting with Daytona in the US and later UK cases used a different kickstarter mechanism. Daytona could use either kickstart mechanism, I was told back in the day that the gear on the “Daytona style” kickstart mechanism which on this new design was not constantly engaged with the idler gear like the earlier mechanism, in racing had slid over and engaged on some racers so common practice was to retrofit the old system when using “Daytona’ cases. I did have one customer that would not take no for an answer so I used a cut down throttle slide return spring to keep the kickstart gear positively disengaged when not in use. One drawback with the “Daytona” style kickstart mechanism is that it does kick over more slowly . This style also used a “single” offset idler/tach drive gear instead of the 2 gears pressed together of the earlier style.
EarlyTZ’s used this “double gear” also but ran it with a needle bearing. Later RZ’s used the “single” gear but added a bushing to it
Since Daytona and later RD’s used the single gear kickstart idler gear they used a longer tach drive shaft, a smaller nylon tach drive gear and a different tach drive ratio
TZ250 and 350 had different primary gear ratios than the RD’s so they used 2 different nylon tach drive gears (and 2 different water pump drive gears)
While the rest of the world got electronic ignition in 79/80 the US didn’t
The Daytona, got a new crankshaft without the dreaded lead weights but improper heat treating it’s believed caused them to snap the center section under racing conditions
Later UK RD400 and RD250 did get this style of crankshaft though with the larger LC/RZ style ignition taper for the electronic ignition they got but I’m told those did not have the racing center crankshaft snapping problem.
LC’s went a step further and went to the now well know RZ/Banshee style crankshaft but the LC’s still had a 16mm wide big end bearing (RZ widened to 17) with larger big end and wrist pin bearing outer diameters
An LC crankshaft will fit in Aircooled RD cases, but you need to mod the end of the crank, OR 'doghouse' the RH cover to take the longer crank. (no oil pump can be used after this mod) the LC crank also allows for a large taper cdi to be used, and yes, an RZ or LC cdi will then bolt right on to aircooled cases. you will need to clearance the LH cover to accommodate the cdi pickup though
An RZ crankshaft is aprox 2 mm too wide to drop right into RD/LC cases but have been made to fit.
The keyway on a Daytona crank is 90 degrees off the LC and RZ cranks
RZ cylinders while will “slip in” to RD cases but have a much different cylinder base stud pattern, the cylinder center to center spacing and heights are the same as a RD and LC 350 they just won’t bolt up
The RZ right side cover/water pump will not work on an RD set of cases because they are missing the rear water pipe passage and the boss to support the pump shaft
RZ and LC have a longer right crank snout than an RD to take the water pump drive gear
Some have used the wider RZ rods on RD cranks by machining .5mm off the inside of each crankweb
An RZ clutch cover will almost fit onto an RD set of cases but the RZ have a little more metal in two places Teazer
An RD clutch cover can be made to run a TZ water pump, the TZ waterpump will be driven through the original oil pump drive shaft hole, but it does require an adapter to fit under the pump
LC and RZ use the same kickstarter arrangement/mechanism. Similar to the Daytona and later UK RD’s On the RZ/LC the inner end of the kickstarter shaft is a smaller diameter than RD‘s, so either the cases needs to be bushed or a sleeve pressed onto the shaft. The outer portion of the shaft is longer than an Air cooled motor which is fine if you use an LC or RZ clutch cover. This can only directly be done on Daytona and later UK cases as there is a different style locator spring boss in those cases (unless of course you weld and machine the cases)
Twice to use an LC side cover I grafted two early style RD kickstart shafts together to extend the kickstart mechanism the needed 17mm.
You can run RZ/Banshee primaries on an RD I’ve done it many times
The Daytona and later left side covers had a provision for the electronic ignition pickup
The Daytona had thinner primary gears
The Daytona 5th and 6th gears had thinner engagement dogs which made them easier to shift into these gears but not good for racing
The Daytona and later used a different shift mechanism ratio
76-78 US RD400's had a small cutout at the bottom of the skirt on the exhaust side for emissions reasons that actually let ex gasses into the crankcase at TDC The Daytona did not have this cutout because it used vacuum controlled external exhaust butterfly valves to accomplish the same result so the trick was to use Daytona pistons in all the 64-65mm bore RD's at least until RZ (and LC) pistons came out.
76-78 US Rd400's also came with an small exhaust bleed port in the roof of the exhaust port approximately 10mm above the port, in performance applications it's standard practice to plug and weld these closed
All year RD350's in the US had Dykes ring pistons (not good for racing)
An RD400 left side cover will fit an LC perfectly, you just have to make some room for the electronic ignition trigger for the LC Jspooner
The LC and RZ bottom ends are very similar
The crank width was the same from RD to LC but they did widen the trans gearset making the gears wider
The RZ crank width increased slightly (approx 2mm) and with it another increase in gearset width and shift drum. Gears differ but the RZ uses a few of the LC‘s gears I counted 3 with the LC 4L0 prefix, both changed to the “shiftstar” type gear change mechanism. LC and RZ crankcase mount dimensions are the same, but differ largely than the aircooled RDs. LC/RZ engines have 2 mounting points, aircooleds have 4. Aircooled RD’s had a first gear needle roller bearing were the LC went to a bushing there Tacky/Dusty
LC and RZ transmissions use three shift forks and not 4 as in the RD’s
Unlike the RZ, LC’s still had the clutch pushrod that went all the way through and out the left side of the cases to a clutch actuator in the left side cover
LC/RZ use the same shift forks . Tach gear assemblies are the same LC and 83-84 and US 85 RZ . Clutch basket/ primary gears are interchangeable. Clutch hub , LC clutch cover will fit the RZ , same gasket for both . Oil pump are interchangeable , 1979-80 RD400 2R9 , LC and RZ . Coolant pump , LC and RZ . Reed valves , RD350 , RD400 and LC plus RZ500 . Carburetor manifold and balance tube ,1979-80 RD400 2R9 and LC . Motor mounts with spacers , LC and RZ and stays under the motor to the frame Zedixie13
Here are some engine model differences between US and UK 250/350/400's from a European viewpoint
RD250/350. Euro 351/352 models have a blocked 6th gear (different pawl plate in selector segment pins)
RD250/350B. Euro 521/522 models have 521 cylinder heads and gearbox. The gearbox has all 6 speeds available and has the same ratio's of the later 250/400 with overall closer ratio's
RD250/400C/D. Euro 1A2 (250) and 1A3 (400). Similar to 1A1. Gearbox shafts have later type splines. Cylinder heads are marked 1A0 (250) and 1A3 (400), different casting to 1A1
RD250/400E. 2R8/2R9. "TZ" style crank with no lead weights and slotted rods. Revised cylinders, porting and CR. Revised 400 pistons without front cut-out in skirt. CDI ignition. Revised LHS case cover with bulge over CDI pick-up coil. Gearbox and shifter changes. Narrow primary gears. Small “LC” X-over tube on 400. 5Port
Banshees had different transmission gear ratios than the RZ most everything else interchanges between the two
RD250/350/400 Performance Parts Upgrades
RZ350 or Banshee pistons are a far superior piston than the stock RD pistons.
Of the cast pistons OEM are arguably the best, then Vertex, then Pro-X
Of the forged pistons Wossner, then Wiseco
The center tab at the bottom of these pistons must be removed thought (very easy),
And Vertex must be trimmed a bit if used in an RD400.
For Racing Bigbore Topends (66mm and up)
1980 IT/DT 175 pistons or Yamaha Blaster Pistons. Either piston is 5-6mm shorter than stock and requires machining the top & bottom of the cylinder to compensate for the height. The blaster pistons also have a 10deg piston dome instead of the RD/RZ/IT/DT 15deg so it does require reccutting the cylinder heads (but if your doing a bigbore you need to recut the cylinder heads anyway)
Sleeving these cylinders is not ideal because of the decreased heat dissipation from the pressed in replacement sleeve and the fact that the thickness of a replacement sleeve cuts into the already limited transfer port tunnel area.
There have been some Extra Big Big Bore cylinders done with H2 pistons and sleeves. JR
The Crankshaft
For High HP applications Shot Peening the connecting rods is recommended
2T2 rods are the best of the OEM rods
Need Hollow crank pins? I use Kawasaki 13035-1010-01
Big End Bearings
I used TZ750 big end bearings in my landspeed bike but there were less options then
93310-422BO “TZ125 big end bearings” Coyote
Suzuki RG500/RM125 bearings 09263-22060 Lyn
Suzuki RM125 RG500 Wiseco part number is B1047 Supertune
I use OEM RG500 Big End Bearings 09263-22060 for all out racing and Wiseco RG500 part# B1047 for EVERYTHING else
Crankshaft Main Bearings
73-80 TZ250/350/750 outer roller bearings part number 93310-00012
but these days hybrid ceramic bearings are the way to go
Exhaust Flange Gaskets
76-78 US spec cylinders use Suzuki 14181-01D00 They have a larger I.D.
A newer option though is to use Blaster exhaust flange gaskets Supertune
Clutch Friction Plates
“1981YZ250H,1983 XS400, 1986 FZ600S, 1992 FZR1000D. XS400 plates work especially well” Dave
“FZR1000 friction plate have about 40% more surface area” M in SC Clutch
RZ350 (more surface area than the RD400 because they didn't use the large rubber "cushion rings" to reduce noise)
Steel Plates Earlier RD250/350 steel clutch plate didn't have "The balancing notches" so have more surface area or Barnett
The RD250/350 had a 6 plate clutch but that can easily be swapped out for the later 7 plate clutch
if you put an RD400 trans in an RD250/350 with the 400 clutch you will have to clearance the inside of the RD250/350 right side engine cover, or I've heard you can use a thicker side cover gasket.
There are different clutch and sprocket splines on the RD250/350 than the RD400 transmission
RZ350/Banshee Clutch Basket and Primary Gears fit right on to Rd’s
Dry clutch conversion
I’ve heard that HB used YZ490 parts to do this conversion
TZ250/350.(Takes a little work) Use the clutch and primary sidecover. This requires a longer mainshaft, but the stock TZ mainshaft has a higher first gear than the RD’s and is part of the main shaft so you can either run the TZ transmission with higher first gear and close ratios or get a special mainshaft from this company: www.yamaha-tz-classicracing.de/uk/teile_getriebe.html that allows you to use an RD transmission with the TZ dry clutch parts. The TZ dryclutch cover didn’t come with a provision for a kickstart mechanism but I have seen several of these covers modified to use a kickstarter. I've used a billet LC cover by Metemachex to do this with a kickstarter but you have to extend the kickstart shaft 17mm. NOW Fondseca makes a dryclutch cover with the kickstart provision
Transmission
It is highly recommended for racing that you get your transmission undercut by a company like R&D Motorsports. R&D also does transmission micro polishing and anti friction coating
“According to Yamaha service bulletin 259 any spinning gear should have between .003” to .005” side play for maximum efficiency. Too little clearance and it will bind, too much and the gears can pop out of engagement causing the dogs to become rounded. Select the proper size shim and install it so the spinning gear is moved toward the sliding gear that engages it. Sizes are 20.2x33x.5,.6,.7,.8,.9, and 1.0mm (137-17427-00-05). And also 25x34x.3 and .5 (168-17428-01-03)” LynReeds
Reeds and Reed Cages our options are:
Use the stock reedcage with a single petal reed from TDR or 93-2012 YZ85 reeds trimmed down just slightly at the front. These are a single petal reed but thinner than the TDR petals Or
1986 YZ125S reeds. “These are a 3-petal reed cut one petal off to fit your stock cages. Part number 55Y-13612-00-00” MBSteve
Stock cages are good for up to 70hp.
Modify your stock reedcages by removing the center divider and using single petal reeds, this works great for 80% of the RD’s out there,
If your extensively modifying your stock reedcages ask for the Harry Barlow cut it‘s a tapered reed that completely covers the reedcage surface area
Stock YZ85 reedcages
V-Force YZ85 reedcages. Part number V382A (Use AG472A stuffers) Afhaldeman
RZ350 reedcages
RZ350/Banshee V-force reed cages
My favorite for 90 percent of RD applications is stock YZ85 reedcages with either stock reeds or TDR racing reeds part# 88-EE or V-force YZ85 reedcages.
Anything bigger than this and major surgery to your cylinders or replacing the whole intake reedbox is required
Intake manifolds
RZ350 are a nice improvement and allows you to use an intake crossover tube or boost bottle. You can also get aftermarket RZ manifolds without the crossover
Tz750 intake manifolds P/N 409-13565-00 are discontinued but TZ Mike does make very good quality reproduction manifolds.
Racing Ignitions
Motoplat
PVL
HPI Racing
HPI also makes a small external rotor ignition with lighting (M in SC)
ProFlo (No longer available)
TZ250/350
MZB
MZB also makes a CDI ignition with lighting
If you just want to eliminate your points which is ALWAYS an improvement Vintage Smoke makes a DYNA ignition kit that bolts right on.
RD400 Model Codes
USA Daytona Model code 2V0
Canadian Daytona model code 3J7
Oceana Daytona model code 3M4
76-78 model code 1A1 - all markets
'79 European model code 2R9
The cylinders and heads from a 1A1 will fit all years, as long as they are swapped as a complete set, along with the exhaust pipes. The cylinders, head and head gasket for the 2V0 are unique. The cylinders for the 3J7, 3M4 and 2R9 are the same. The 2R9 had separate cylinder heads and the 3J7 and 3M4 had a one piece head, they should be interchangeable. The 2R9 had separate head gaskets and the 3J7 and 3M4 had a one piece head gasket, but 2R9, 3J7 and 3M4 have the same gasket thickness, so you could use the separate gaskets on the Canadian and Oceana Daytonas
TZR250's
1986-88 2MA - 1KT Case reed forward facing cylinders
1989-90 3MA Reverse Cylinder
Transmission Ratios
TZ250 RD400 RD250/350
.81 .888 .785
.87 .961 .888
.96 1.083 1.040
1.13 1.318 1.318
1.42 1.778 1.778
1.93 2.571 2.571
Primary Gears
RD250 68/21 3.238
RD350/400/LC/RZ 66/21 2.869
TZ250 77/23 3.35
TZ350 74/25 2.96
Cylinder Studs
RD 250 90116-08065-00 90mm(72-73mm sticks out of casing)
RD350 90116-08064-00 97mm (80-81mm sticks out of casing)
RD 400 90116-08232-00 117mm (98mm sticks out of casing)
TZ250 90116-08213-00 94mm
TZ350 90116-08212-00 101mm
TZ750 90116-08212-00 101mm
RD250LC/RD350LC 90116-08219-00 106mm |
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Post by veg on Aug 2, 2019 8:30:02 GMT 1
V interesting that must have take some time. Enjoyed reading that, thanks.
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Post by oldbritguy on Aug 2, 2019 9:58:53 GMT 1
Well done on a considerable bit of research. As Veg says a very interesting read with some options for improving or upgrading components in existing models.
Is this being published as part of a larger piece of work?
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Post by Tobyjugs on Aug 2, 2019 10:52:30 GMT 1
Wow that is very handy info.
I wish I could've read this first before I started playing with the LC and RZ crankshafts. It would of saved me a lot of head scratching.
Not sure if I missed it in your explanation as it is very comprehensive.
The center of a LC crankshaft is 2mm wider than the centre of an RZ crankshaft
Does EE stand for Ed Erlandbach?
If so thank you for your website as I have visited it many times for info
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ee
Newbe
Posts: 3
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Post by ee on Aug 3, 2019 4:21:14 GMT 1
Yes Ed Erlenbach. Aprox 2mm wider total width, I don't have an RZ crankshaft here at the moment to measure but a good friend and an amazing tuner that does the conversion fairly regularly machines .8mm off each outer crankshaft bearing surface. Ed
I wish we'd gotten LC's (non PV) here in the states or that there were more here they would be fun to work with, I'm not crazy about the PV's. |
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Post by Tobyjugs on Aug 3, 2019 6:11:45 GMT 1
Yes Ed Erlenbach. Aprox 2mm wider total width, I don't have an RZ crankshaft here at the moment to measure but a good friend and an amazing tuner that does the conversion fairly regularly machines .8mm off each outer crankshaft bearing surface. Ed
I wish we'd gotten LC's (non PV) here in the states or that there were more here they would be fun to work with, I'm not crazy about the PV's. The Labyrinth gland is wider on an LC and this makes the centre wider. I've never thought about machining the outside of the crank. I've only done the insides to accommodate the wider +4 rods for fitting in the LC engine. I'm a big fan of the 4LO type engines but I do believe there is a place for both of them. The last two years I've prepared an LC for sprinting over rough ground. In the dry the bike is manageable and it took 1050 Triumph to knock the bike out. This year it was dryish so the track was good at the beginning and the LC's were quick. When the track got churned up the became more difficult to control due to the peaky engines. I have been thinking a RZ engine might be better due to the longer spread of power. |
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Post by liffy16 on Aug 3, 2019 8:56:25 GMT 1
Shame you did'nt get the lc as yes the powervalve is a quicker bike there's no denying that,but the lc is such fun to ride peaker engine yes added to a lighter chassis just makes them that way !!Supppose that's what makes them so iconic
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