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Mohawk last won the day on September 14

Mohawk had the most liked content!

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About Mohawk

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    Race Team Owner

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  • Location
    Bristol, UK
  • In My Garage:
    VFR800Fi Y2K, 120hp, minus 30Kg = VFR800R

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  1. Err no I meant 0.1mm as in one tenth of a mm extra lift would not cause a noticeable difference on a dyno. Anything in the 100th of a mm would not be noticeable anywhere.
  2. The reason tighter is considered better is because you get more valve lift, thus in theory more power, but 0.1mm will not show on a dyno. The second reason is no cam banging across the excessive gap. Best to adjust using move around & get as close to centre of range with what you have & minimum number of new shims. But each to their own.
  3. So the 5th gen VFR only has a single pintle injector. The 4 hole is a major improvement over this & the CBR929 injectors are a drop in fit. The 6th gen uses 12 hole injectors, but the research I have done seems to indicate from empirical evidence that the change from 1 to 4 hole is really good but the step from 4 to 12 less so. The later larger hole count injectors seem to be more about reducing emissions than improving performance. If there was a readily available 12 hole that would fit then I would have tried them. There are some rather expensive ones designed to fit Hayabusa's which used the same single hole injectors as the VFR. but $500 seemed a bit steep for an experiment ! Maybe if the 4 hole prove to be a good upgrade then I might entertain those expensive ones but not if they don't at least double the gain from the 4 hole injectors. I just did about 50 miles today & as per the last time I used s zero map on the RBR the bike was very fluffy at the beginning. After the 50 miles of O2 auto fuel correction, the seat of the pants feel is really good. I'll get another 50-100 mes on it then get it dyno'd. Looking at the fuel correction tables, where the stock fuel pressure was adding up to 35% more fuel, the new setup has reduced many cells, so injector delivery is working as intended now. But importantly the cells that matter in the mid range to highend are adding or not removing fuel duty cycle, so more air must be flowing. The bike picks up really well now in any gear from any revs in sny gear, where ss with the lower fuel pressure it always seemed to lag a bit !
  4. The axles don't tend to wear out but the rear hub bearings it runs in can wear out. I replaced mine last winter, as it was an advisory at the MoT in the summer. That was at 62K miles. Like you I had stripped & greased it around 38K miles. The ball bearing end wore out, so I replaced all the hub bearings. If there is no play detectable, then just strip, clean & regrease every 20-30k miles.
  5. The one advantage to the best bike in the world is that Honda sold bucket loads of them. Thus secondhand parts are easy to come by. Plastics are harder to find ! So buy the queen. Give it a full overhaul & then ride it like ya stole it ๐Ÿ‘๐Ÿ˜€
  6. I put a radius on the inlets at the base of the box, so they are effectively the short or primary stack. The dual or secondary stack is the one above with the mushroom lip. So still dual stack. Plus the inlets are wider now & tapered to the butterflies, so should widen the torque curve further whilst improving top end flow & the new injectors should provide a better atomisation at all rpm, which is supposed to help torque, power & mpg. ๐Ÿ‘
  7. Looking much more like the real deal ๐Ÿ‘๐Ÿ˜Ž
  8. Finally got all the bits to fit my uprated FPR to complete my throttle body & airbox upgrade. Then updated my other threads about both elements ๐Ÿ‘
  9. So having forgotten to take pics of the Mk2 airbox, I was fitting a new FPR today & remembered to take some. Pics above show Mk1. Below id the Mk2. I used a spare airbox & rounded the intakes to a 6mm radius, which is the minimum recommended intake radius. I then adjusted the dual stacks to suit the new intake height. This is matched to reworked throttle bodies which now taper from 42mm to 36mm. matching the optimum intake taper angle. These are fitted with CBR929 4-hole injectors, which require 51psi at idle or 4bar (58psi) peak. I will put a few miles on the bike to get the fuelling sorted for the new setup, then get it dyno'd & see what we have.
  10. I did order 3 of those, but all 3 were not delivered & cancelled by the sellers ! So after much searching I came across this small unit. "Saxon M/spt Silver CNC Machine Housing for Bosch Fuel Pressure Regulator Jenvey" on the bay. So with a few AN-6 adaptors & converters I was able to do this. Before After All sealed & adjusted & now 4bar pressure to suit the CBR929 4-hole injectors requirements. I've set the RBR to a zero fuel map & will do some miles & see how it adjusts.
  11. Skinny tires handle the best. I had an ANF125 (modern C90) as a winter run around a few years ago. I used to think my CBR600F4 handled well, until I rode the chicken chaser. It may not be fast but what a blast, in the wet on the roundabout near my work I could get it into a two wheel drift at 30mph, fantastic. After a few months riding that in the winter, getting back on the CBR was like steering a barge. So donโ€™t knock skinny, they definitely handle the best ๐Ÿ™‚
  12. That Apache gunner was just checking with control is that old red bike really the target. Iโ€™ve flown one of those Jet Provost jets with a display pilot. One of his stunts is to take off, retract the gear, then fly lower over the runway at about 2ft altitude ! I always liked the look of the 400, I had a 500 for many years, sold it to a mate. I think he still has it, if I ever get the spare time & cash Iโ€™ll try to get it back one day.
  13. All depends on how high you want them to be ? I raised mine 12mm by removing the stock 5th gen clip ons & drilled a 4mm hole into the base of the anti twist locator stud. If you are really keen you can tap the hole & use a longer bolt in it. I just used a 20mm long 4mm socket head bolt. This is just glued in and rests on the clamp bolt when the clip on is in place. A longer bolt will allow a different height. My forks are 10mm higher through the clamps, so this just puts the bars back to the stock position. But crucially retains the anti twist function. To fill the gap below the clip on I used three 38mm O-rings.
  14. Iโ€™m not sure if that info is publicly available, but the VFR in it various guises was one of Hondas best selling bikes globally for many years. I know a man who may know or be able to get the answer Iโ€™ll pose the question to him. If you look here it explains the serial number system https://itstillruns.com/decode-vin-number-honda-motorcycle-5776052.html So based on that no more than 1 million are catered for per year. Iโ€™ve found complete model serial number ranges for some of the rarer model, but not the common ones. CBR600 out sold most other models globally for many years. I know in the UK we have the how many left website that lists all still registered models. https://www.howmanyleft.co.uk/?utf8=โœ“&q=Honda+VFR800&commit=Search which shows 6,500 5th gens registered in the UK between 98-02, of which over 3,100 are still on the road & another 2,600 are registered but off the road, so still exist in some state of disrepair or not currently used. Not sure if Canada/USA have a similar site.
  15. Welcome, anything you need to know will be answered by the very knowledgeable crowd on here. Throw up some pics of the bike & what you have done to it, sort of before & after shots are good.
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