UK Monster Owners Club Forum » .: Technical :. » Mods & How To's » M900 mudguard crack

Reply
 
Thread Tools Display Modes
Old 10-02-2020, 10:00 AM   #1
the lodger
Registered User
 
the lodger's Avatar
 
Join Date: Oct 2019
Location: Chorley
Bike: M900
Posts: 160
M900 mudguard crack

My front mudguard has split from the mounting hole to the edge ....about 1 cm. The mudguard seems fairly secure otherwise via the other 3 good fittings but it strikes me that I should have a go at repairing the crack. Is this a fairly common problem on these older bikes ? I seem to remember reading something about being careful with the fittings. Anyway what would be the best way to repair this ? Would my go to solution of superglue work on what I assume is plastic ? Thanks
__________________
Contents may settle !
the lodger is offline   Reply With Quote
Old 10-02-2020, 10:35 AM   #2
Darkness
.
 
Darkness's Avatar
 
Join Date: May 2007
Location: Stockbridge
Bike: M900
Posts: 1,984
Quote:
Originally Posted by the lodger View Post
My front mudguard has split from the mounting hole to the edge ....about 1 cm. The mudguard seems fairly secure otherwise via the other 3 good fittings but it strikes me that I should have a go at repairing the crack. Is this a fairly common problem on these older bikes ? I seem to remember reading something about being careful with the fittings. Anyway what would be the best way to repair this ? Would my go to solution of superglue work on what I assume is plastic ? Thanks
Cracking at the mounting holes was a common problem on the earlier front mudguards, especially if unshouldered fixing bolts are overtightened crushing the part. A fix is to make some sandwich plates to span between the two fixings on each fork leg and glue these in place.

The mudguard design was changed (‘96ish?) to thicken the plastic at the mount. The mount is more wedge shaped, giving a smoother joint with the fork leg.

The next change was 2000ish when the brake calliper fixing bolts increased their centres and the mudguard mounting became two pairs of nylon bands. Those have different fixing centres from the earlier ones, though can be fitted if you make pairs of plates with three holes in each: one to bolt to just the fork leg, one to just the mudguard, and one to both the mudguard and the fork leg.
__________________
Original and Best since 1993
Darkness is offline   Reply With Quote
Old 10-02-2020, 05:13 PM   #3
350TSS
Too much time on my hands member
 
350TSS's Avatar
 
Join Date: Jan 2013
Location: Shipbourne
Bike: M900
Posts: 1,417
A good clean inside and a 40W soldering iron with a screwdriver type tip and a red tie-wrap you should be able to weld it. I managed it on my ZX9R front mudguard which is notorious for cracking.
I do not always like what this bloke does but sometimes it is useful to see a technique tried out.
https://www.youtube.com/watch?v=gRCMIDILfEI
350TSS is offline   Reply With Quote
Old 10-02-2020, 05:58 PM   #4
350TSS
Too much time on my hands member
 
350TSS's Avatar
 
Join Date: Jan 2013
Location: Shipbourne
Bike: M900
Posts: 1,417
PS it's a good idea to position a vacuum cleaner nozzle near the workpiece to take the fumes away as I am sure they are not healthy.
350TSS is offline   Reply With Quote
Old 10-02-2020, 06:00 PM   #5
350TSS
Too much time on my hands member
 
350TSS's Avatar
 
Join Date: Jan 2013
Location: Shipbourne
Bike: M900
Posts: 1,417
PPS "Since pure ABS contains no halogens, its combustion does not typically produce any persistent organic pollutants, and the most toxic products of its combustion or pyrolysis are carbon monoxide and hydrogen cyanide." Google is your friend - Sometimes.
350TSS is offline   Reply With Quote
Old 10-02-2020, 06:14 PM   #6
Flip
Registered User
 
Flip's Avatar
 
Join Date: Mar 2010
Location: Beachtown
Bike: M900
Posts: 2,188
If you don't fancy using the soldering iron technique I've found two part epoxy (such as Araldite) works well on ABS, especially if you can open the split to get some on the faces of the crack and then build it up on the hidden face to strengthen it.
__________________
You're perfect, yes, it's true- But without me you're only you!
Flip is offline   Reply With Quote
Old 10-02-2020, 08:44 PM   #7
The Clockie
Guest
 
Posts: n/a
I'd agree that some bracing would be good, but look at Q-Bond for the adhesive/solvent weld. It uses superglue with a catalysed filler powder that produces local heat and softens the base material as the adhesive bites into it. Seems very good!

Nick
  Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 05:45 PM.

vBulletin Skins by vBmode.com. Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.