FYI ... the screws used on Honda bikes needs a JIS Japanese Industrial Standard driver. A ASE Phillips is a different animal that's why everyone strips them out!!!
Thanks for bringing this up, a very important point! Japanese manufacturers have traditionally used JIS screws. They come loose without damage if you use JIS screw drivers and not a Phillips head type. In this video, I should clarify the need for JIS drivers on tight screws. I do manage to loosen the carburetor float bowl screws using a quality Phillips screwdriver. On stubborn engine case screws, the traditional approach has been an impact driver with JIS tips, tapping with just enough force to loosen the screws. My impact driver set has JIS bits, which readily loosen and preserve case screws. JIS drivers work properly and generally protect the screw heads for reuse...JIS screwdrivers ($$$) and bits are available at Amazon.com. Search under the keywords "JIS screw drivers"...I've added these details at the video description.
@@MotorcycleTechandTravel I found that you can enrich the idle circuit by leaning the bike over to the right for cold start, otherwise it's a one kick operation.
How do you keep the piston at TDC during the leak down test? I saw the still with the drill bit wedged into the sprocket, but I didn't notice it there during the panning shot shortly after when the test was being conducted. I've struggled to find a way to keep the piston exactly at TDC when applying air pressure. Even a few degrees rotation at the countershaft is enough to send the engine spinning.
Yes, just as a backup, I did use the drill bit shank to keep the chain/sprocket and crankshaft from rotating when applying the air at TDC. (Spark plug removed, the drill bit shank and sprocket can be aligned with TDC by releasing and applying the clutch lever with the transmission in gear.) The timing mark TDC position on the flywheel is reliable but not easy to identify. Be sure you are aligning the TDC mark and not a spark advance mark...Another way to find exact TDC is with a dial indicator. A two-stroke timing set enables installing the dial indicator and stem or roller tip directly into the spark plug hole with the valves all closed (piston at TDC on its compression stroke). You can find exact TDC with the dial indicator. With the piston precisely at TDC, the applied air should not push the piston downward. This exact rock-over position will not allow the piston pin to force the rod downward. The piston stays here unless the crankshaft moves the rod's angle to an offset position...Be sure to use the PSI recommended for your leak down tester. That pressure setting may be lower than your air tool line pressure.
I am running the equivalent of the HRC kit. My bike was a "Federal" (49-State) model and did not have the D-shape restriction in the intake manifold nor the excess emissions hardware like a California model. The bigger tailpipe outlet (shown in this video) is like the HRC. I am running a Stage 1 HotCams camshaft, which is mild and not significantly impactful on jetting. Compression is stock 10:1 with a new piston and rings running in a fresh chrome-moly iron cylinder from L.A. Sleeve. Also, my tune is for a 4,000 feet elevation baseline. By the chart, I am running the right main jet if we begin with the HRC or a stock non-U.S. XR650R's 175 main jet at sea level. With the 165 main jet described in the tuning video, I should be able to run at low desert or even sea level without damaging the engine. The needle remains clipped in the third groove from the top (like stock), now with a 65 slow jet (like stock)-again for this altitude. The engine ran well with the 68 slow jet and still runs great with the 65 at this altitude. (All fuel flow transitions are smooth and seamless, no bog or hesitation.) Keep in mind that I use the Pulstar spark plug. Even with the previous 172 main jet and 68 slow jet, I could run to 8,000-plus feet elevation without fouling the spark plug. It did run richer, but the plug fired through the richer mix. I was unaware of enrichment unless the spark plug was removed for inspection...In testing the performance with the 165/65 jetting and 3rd needle groove from top combination, it's working very well, especially at our base altitude of 4,000 feet...I trust this is helpful. Thanks for your subscription!
Though both engines are liquid cooled, the cylinder and head layouts seem dramatically different. (Compare the head gaskets and the valvetrain/camshaft mechanisms.) The Yamaha XT660 five-valve cylinder head is a one-off masterpiece. Later XT660s (4-valve) feature EFI. If practical and feasible, it would be worth exploring how to retrofit an XT660 EFI system in place of the Honda XR650R's carburetion.
@@MotorcycleTechandTravel you mean like installing a injection system on the xr650r?. i have been looking into this. the xr revs out on 7000 or 8000? so the direct injector would be the advantage.. the trx700xx is a xr650r with injector trottlebody and bigger cylinder and it outputs like 55 hp. to even get a injector to outpreform a carb you need as many sensors as the ktm 690 have. what a nightmare. you even need to upgrade the xr650r stator to even run the electronics. unless you can find some super high end parts that can run on low voltage
You raise interesting points about an EFI "conversion". There would be an oxygen sensor requirement in the exhaust stream (not a deal breaker) and, as you note, a need for higher stator output and a battery to handle the fuel pump, a throttle body, an ECM/ECU and any necessary sensors. There are available stator upgrades and rewinds that will boost the stator output. EFI would also require electric start to provide a consistent, adequate crankshaft position signal and EFI pulse. Any EFI system needs a crankshaft position sensor and coolant temperature sensor. Systems use a MAP sensor or mass air flow sensor, depending upon whether the design is speed density or mass air flow...I have been around automotive EFI conversions for decades. (One example is the Jeep/Mopar EFI retrofit for the AMC/Jeep CJ and YJ 258/4.2L inline six. There have been a number of "generic" throttle body and port/multipoint aftermarket EFI retrofit systems.) As for motorcycles, I have not worked with systems like the Yamaha XT660 or the later Kawasaki KLR although these engine displacements and single cylinder designs would provide the right volume air-fuel flow. It would be exciting to attempt this kind of conversion. To the point, however, there would need to be a real incentive and budget. The electric start conversion from C-Fab, in itself, would be a considerable expense. A donor KLR or XT660 would be needed. If done with commercial intent, there would need to be enough willing XR650R customers to justify the research, development (R&D) and production costs.
FYI ... the screws used on Honda bikes needs a JIS Japanese Industrial Standard driver. A ASE Phillips is a different animal that's why everyone strips them out!!!
Thanks for bringing this up, a very important point! Japanese manufacturers have traditionally used JIS screws. They come loose without damage if you use JIS screw drivers and not a Phillips head type. In this video, I should clarify the need for JIS drivers on tight screws. I do manage to loosen the carburetor float bowl screws using a quality Phillips screwdriver. On stubborn engine case screws, the traditional approach has been an impact driver with JIS tips, tapping with just enough force to loosen the screws. My impact driver set has JIS bits, which readily loosen and preserve case screws. JIS drivers work properly and generally protect the screw heads for reuse...JIS screwdrivers ($$$) and bits are available at Amazon.com.
Search under the keywords "JIS screw drivers"...I've added these details at the video description.
In oz at sea level 65s pilot and 168 main needle 4th clip position. Std piston,cam aftermarket exhaust uncorked just lovely.
Needle is the completion version.
Sounds good...If your 1/8th to full throttle makes smooth transitions, you nailed it!
@@MotorcycleTechandTravel I found that you can enrich the idle circuit by leaning the bike over to the right for cold start, otherwise it's a one kick operation.
Yea...We want these kickstart-only bikes to fire immediately, especially when traveling single track. Sounds like great tuning!
How do you keep the piston at TDC during the leak down test? I saw the still with the drill bit wedged into the sprocket, but I didn't notice it there during the panning shot shortly after when the test was being conducted. I've struggled to find a way to keep the piston exactly at TDC when applying air pressure. Even a few degrees rotation at the countershaft is enough to send the engine spinning.
Yes, just as a backup, I did use the drill bit shank to keep the chain/sprocket and crankshaft from rotating when applying the air at TDC. (Spark plug removed, the drill bit shank and sprocket can be aligned with TDC by releasing and applying the clutch lever with the transmission in gear.) The timing mark TDC position on the flywheel is reliable but not easy to identify. Be sure you are aligning the TDC mark and not a spark advance mark...Another way to find exact TDC is with a dial indicator. A two-stroke timing set enables installing the dial indicator and stem or roller tip directly into the spark plug hole with the valves all closed (piston at TDC on its compression stroke). You can find exact TDC with the dial indicator. With the piston precisely at TDC, the applied air should not push the piston downward. This exact rock-over position will not allow the piston pin to force the rod downward. The piston stays here unless the crankshaft moves the rod's angle to an offset position...Be sure to use the PSI recommended for your leak down tester. That pressure setting may be lower than your air tool line pressure.
168?.. does it have hrc kit or not?
I am running the equivalent of the HRC kit. My bike was a "Federal" (49-State) model and did not have the D-shape restriction in the intake manifold nor the excess emissions hardware like a California model. The bigger tailpipe outlet (shown in this video) is like the HRC. I am running a Stage 1 HotCams camshaft, which is mild and not significantly impactful on jetting. Compression is stock 10:1 with a new piston and rings running in a fresh chrome-moly iron cylinder from L.A. Sleeve. Also, my tune is for a 4,000 feet elevation baseline. By the chart, I am running the right main jet if we begin with the HRC or a stock non-U.S. XR650R's 175 main jet at sea level. With the 165 main jet described in the tuning video, I should be able to run at low desert or even sea level without damaging the engine. The needle remains clipped in the third groove from the top (like stock), now with a 65 slow jet (like stock)-again for this altitude. The engine ran well with the 68 slow jet and still runs great with the 65 at this altitude. (All fuel flow transitions are smooth and seamless, no bog or hesitation.) Keep in mind that I use the Pulstar spark plug. Even with the previous 172 main jet and 68 slow jet, I could run to 8,000-plus feet elevation without fouling the spark plug. It did run richer, but the plug fired through the richer mix. I was unaware of enrichment unless the spark plug was removed for inspection...In testing the performance with the 165/65 jetting and 3rd needle groove from top combination, it's working very well, especially at our base altitude of 4,000 feet...I trust this is helpful. Thanks for your subscription!
@@MotorcycleTechandTravel do you think a 5 valve top from xt660 would fit a xr650r?
Though both engines are liquid cooled, the cylinder and head layouts seem dramatically different. (Compare the head gaskets and the valvetrain/camshaft mechanisms.) The Yamaha XT660 five-valve cylinder head is a one-off masterpiece. Later XT660s (4-valve) feature EFI. If practical and feasible, it would be worth exploring how to retrofit an XT660 EFI system in place of the Honda XR650R's carburetion.
@@MotorcycleTechandTravel you mean like installing a injection system on the xr650r?. i have been looking into this. the xr revs out on 7000 or 8000? so the direct injector would be the advantage.. the trx700xx is a xr650r with injector trottlebody and bigger cylinder and it outputs like 55 hp. to even get a injector to outpreform a carb you need as many sensors as the ktm 690 have. what a nightmare. you even need to upgrade the xr650r stator to even run the electronics. unless you can find some super high end parts that can run on low voltage
You raise interesting points about an EFI "conversion". There would be an oxygen sensor requirement in the exhaust stream (not a deal breaker) and, as you note, a need for higher stator output and a battery to handle the fuel pump, a throttle body, an ECM/ECU and any necessary sensors. There are available stator upgrades and rewinds that will boost the stator output. EFI would also require electric start to provide a consistent, adequate crankshaft position signal and EFI pulse. Any EFI system needs a crankshaft position sensor and coolant temperature sensor. Systems use a MAP sensor or mass air flow sensor, depending upon whether the design is speed density or mass air flow...I have been around automotive EFI conversions for decades. (One example is the Jeep/Mopar EFI retrofit for the AMC/Jeep CJ and YJ 258/4.2L inline six. There have been a number of "generic" throttle body and port/multipoint aftermarket EFI retrofit systems.) As for motorcycles, I have not worked with systems like the Yamaha XT660 or the later Kawasaki KLR although these engine displacements and single cylinder designs would provide the right volume air-fuel flow. It would be exciting to attempt this kind of conversion. To the point, however, there would need to be a real incentive and budget. The electric start conversion from C-Fab, in itself, would be a considerable expense. A donor KLR or XT660 would be needed. If done with commercial intent, there would need to be enough willing XR650R customers to justify the research, development (R&D) and production costs.