Friday, 4 March 2022

'the noise' part 2

 The next thing I looked at was the tacho drive, this is a worm style gear and runs at 90 degrees against the corresponding gear on the end of the idler shaft.

The tacho gear seemed to have an excessive amount of vertical play, suggesting the noise could be this gear vibrating up and down? The gear has an upper and lower washer, which the manual highlights to remember to reinstall and an oil seal, which was super hard.

As a test I rebuilt the side case and refilled the fluids without the gear, I cut a rubber finger of my workshop gloves to cover the tacho gear drive hole just in case something went in the motor or oil came out.

I have compiled some clips with various stages to focus on what was the rattle or what is just standard engine noise. I also recorded my MB8 for an engine noise comparison but I didn't include that in the vid, so just MBX.

Tuesday, 1 March 2022

'the noise' part 1

When I originally bought my bike it had an annoying engine rattle, I actually just put it down to an old bike and maybe a little end bearing? 

I wanted the engine fully re-built with a re-bore and this was done via our friends at the M Shop. While the engine was away it had all new bearings and seals as well as the piston, clutch, carb and external finishing. 

When the bike was built and the engine in you can here the engine is smooth, but 'the noise' was still there.

At this point I was not concerned until the kick starter shaft snapped and it got my thinking about replacing any suspected gears and cogs that might cause the rattle. Read about that here 

After that rebuild I anxiously started the bike and the rattle was still there, again I parked it up and thought I would do some more investigating in the new year.

At this point I thought I would speak to the M Shop to quiz them to what they thought was the issue, I'll add I was not implying or blaming them for the continued noise as it was there before re-build and was something weird and not covered by the engine rebuild. The M Shop were as usual very helpful and gave me a few suggestions to look and even offered to have the motor back. 

So the bike came apart again...

clutch removed

water pump bush

idler shaft

So the first thing is the water pump bush is broken and the M shop advised to look at the shat and teeth of the idler shaft. I ordered in the replacement bushing and managed to borrow a idler and water pump shaft just to check and eliminate.

With the bike re-built and started the noise was still there....

idler shaft inspection limits

what's in the RH crank caase

Water pump parts

Friday, 26 February 2021

fuel tank warning stickers

 The finishing touches can make or break a restoration and although my fuel tank was a 'new old stock' tank it lacked the warning labels so it is something I definitely want to add. The first thing I needed to know was which labels are on there as I cannot remember my original bike and the positioning of them. I put a request out on the M Classic Facebook post and Tony and Steve from quickly stepped up to help with a decent top image and all the dimensions.

The next issue is sourcing the decals, the middle decal on the bellow image seems readily available but the top and bottom decals seem to be discontinued? If anybody can point me in the right direction for these I would appreciate it?

Monday, 15 February 2021

Brochure: MBX80 what if?

What if Honda kept making the MBX80 in 1989/90 what would the brochure look like? Just for fun here is my interpretation in the style of the late 80's marketing department using the NS125R brochure for inspiration, what do you think?

inspired by... 

Friday, 21 August 2020

My bike: Tidy up small items

 As with all projects you always have an extensive list of stuff you want to change, maybe its things nobody else will ever see but just bug the cr@p out of you. While I was ordering from CMSNL I took the time to order a couple of those annoying parts.

2 x replacement screws for the speedo fascia

1 x replacement drum brake rocker arm, bolt and nut.

1 x wear indicator and felt.

All small stuff, but progress!



My bike: kick start rebuild

 Ouch... I routinely roll the MBX out the garage, fuel tap on, choke on, foot peg up and prod the kickstarter and snap, the kick start shaft snaps clean against the crank case and takes a little bit of leg with it.

Looking at the owners manual its not a massive job and the kick start shaft can be replaced with the engine in. Also in the owners manual it states that there are service limits not only on the shaft (6) but also the idler gear (2), inspection on the oil pump gear (1) and both kick start springs (8 and 5), so I decided to replace the lot including the collar (9), ratchet (4) and ratchet gear (3).

For availability all parts were bought via David Silver Spares and CMSNL

On to the repair...

First drain both the coolant and gearbox oil. Tip, remove the rad filler cap!

Remove the rev counter cable and clutch cable and remove the right hand side cover. Tip: pay attention to the clutch actuator pusher on the inside of the case!

To just do the kick start shaft you don't have to remove the clutch, but as I needed to replace all the gears the clutch had to come off. NOTE: If you do take the clutch off the balancer shaft does need to be timed to the primery - see bottom of the page!

plastic oil pump gear, check for wear and tear.

To re-fit the new idler gear you will have to remove the ratchet plate 

Refitting the kick start shaft and getting the spring tension can be testing... 

Don't scrimp and fit a new gasket

Ratchet assembly, next is to get the correct clocking and spring tension. 

here is the clocking and alignment from the manual.

Monday, 15 June 2020

FWD-F: Twin disc UK 2nd gen model

I while back I had a conversation on our facebook page with an ex-owner who said he had a MK 2 MBX80 (rainbow) bike that was UK specification complete with twin discs. At the time I thought this was super interesting as I knew Honda only brought in the original MK 1 model in black and white for a couple of years, so what could this MK2 be?

The guy mentioned the dealer, Rustys in Scunthorpe and they just so happened to be a customer of mine so I reached out to them to see if they remembered selling the bike, keep in mind this would be 35 years ago. They mentioned they remember selling little Honda's but couldn't pin down any specifics, so I just chalked it down as interesting but without a bike I just had to take the guys word for it.

Fast forward to 2020 and I was contacted by a chap called Mark Roberts who had a UK MK2 bike. Better still the history of the bike is complete, first registered in 1986 on a D plate it was bought from The Honda Centre in Old Colwyn North Wales (now Colwyn Bay Motorcycles). Mark bought the bike in 89, subsequently sold it to a family member then bought it back it now stored and waiting for a light restoration. Apparently there were a few bikes kicking round North Wales which leads me to believe Honda imported a few bikes in 86 for a few specific dealers (like Rustys) who saw there was a demand for the bike but never included it in the official range.

What ever the full story was from Honda we may never know as Honda never nationally promoted the model and it didn't appear in any literature, but seeing some genuine UK MK 2 bikes makes for an interesting foot note in the models history.

Thank you to Mark Roberts for helping fill the gaps in this story and sharing your bike!

According to the parts listing on CMSNL this model is designated FWD-F and as a 1985 model, view the spare parts here:

Monday, 16 March 2020

How Many Left? MBX80 FWDD

According to the website 'How many left', there are 24 MBX80 FWDD's left in the UK, as of today just 7 are currently taxed and 17 are on SORN.

With this in mind I would like to open a register for all remaining FWDD's so we can catalogue all remaining bikes and what condition they are currently on.

If you have one of these bikes (specifically the UK FWDD please) please e-mail me a current photo of your bike and its registration for inclusion on the MBX80 register page. Please also state if you would prefer not to make your registration public and I will withhold it.

A250 PFL

Tuesday, 21 January 2020

My top 10 tips for completing a restoration.

My top 10 tips for completing a restoration.

1/ Have in your mind a clear vision of what you want to do, be it a show bike or tidy run around a clear vision of what you want to achieve will impact each decision you make.

2/ Join a club or group for the model you are restoring. You will see similar machines, get tips and advice and also make some new friends!
3/ Although ebay is great do also look past it for parts, look at where the bike was popular and look for shops in that country as spares will be more plentiful in countries that sold lots of bikes.

4/ If you are going for a factory style restoration, all bikes will need work so a £400 nail really has the same worth as a £900 runner as they will both need similar amounts of money spending on them.

5/ Strip the bike down in groups of parts or sub assembly’s and store all the appropriate parts in storage boxes. 

6/ Do all the power coating or zinc plating in one batch. Many painters or platers will have a minimum charge or batch price, so if you forget something like a side stand you will need to make minimum charge again to get it painted.

7/ Get the frame powder coated ASAP, once this is done you are always in the re-build process and physiologically this is good!

8/ Always do a dry assembly or test assembly before mounting a component properly, there is nothing worse than fighting to fit something with greasy bolts that won’t line up or getting a cable routed the wrong side of something.

9/ Take lots of pictures, buy all the owner’s manuals, workshop manuals and parts books you can find so you can double and triple check cable routing and decal placements.

10/ If you feel a job is to big, don't be afraid to ask for help or employ an expert!

The last thing, so technically number 11 is just to have fun and enjoy doing it!